Contact: Diego Trancanelli (dtrancan -at- unimore.it)

email: dtrancan -at- unimore.it

Title: Aspects of gauge/gravity dualities

ERC-SC: PE2 Fundamental constituents of matter

Type: Theoretical/Computational

ABSTRACT

One of the most revolutionary developments in theoretical physics in the last decades is the discovery of the duality between gauge and string theories, something that also goes under the name of "holography", "AdS/CFT correspondence" or "gauge/gravity duality". I will offer the possibility to study different aspects of this duality, ranging from the more formal ones (like its motivation from string theory, the checks one can perform, etc.) to the more applied ones (like the study of strongly coupled systems in nuclear and condensed matter physics). If time and the student's progress permit, I will also propose some simple, original project to complete the study.



Contact: Diego Trancanelli (dtrancan -at- unimore.it)

email: dtrancan -at- unimore.it

Title: Aspects of supersymmetric gauge theories

ERC-SC: PE2 Fundamental constituents of matter

Type: Theoretical/Computational

ABSTRACT

Supersymmetric gauge theories play a central role in theoretical and mathematical physics, as they are simpler than their non-supersymmetric counterparts and sometimes can be even solved. I will offer the possibility to explore different aspects of supersymmetric gauge theories, like how to obtain exact results (using a technique called "localization") or their relevance in gauge/gravity dualities or other types of weak/strong coupling dualities (like S-duality). If time and the student's progress permit, I will also propose some simple, original project to complete the study.



Contact: Anna Franchini

email: franchi -at- unimore.it

Title: Advanced modeling and simulation of GaAsBi alloys for quantum technology applications

ERC-SC: PE3_5 Electronic properties of materials and transport

Type: Theoretical/Computational

ABSTRACT

Recent studies have shown the huge potential of a material obtained incorporating Bismuth in GaAs for a number of applications to optoelectronics at telecom wavelength, photovoltaics, high speed transistors, etc. because, due to the interaction of the Bi levels with the GaAs valence band the devices would have a very high stability with temperature. This is a narrow gap system very sensitive to the intensity of spin-orbit effects. Also there is a speculation in the literature about the possibility that at low concentrations Bi atoms can form small clusters, which, if true, would lead to the possibility to construct single-photon emitters over a wide range of frequency. This because in GaAs-Bi the valence band shift combines with a large spin orbit splitting leading to a up-shift of states within the GaAs band gap. STM and EXAFS measurements are now underway to reveal the presence of Bi clusters.

This thesis aims at exploring the possibility to stabilize Bismuth defects and small clusters inside a GaAs matrix subjected to a strong biaxial strain, through the use of total energy quantum computations. In particular we aim at exploring the effects of the spin-orbit interactions (both on Bi and GaAs) on the energy gap and optical excitations between the valence and conduction bands as a function of Bi concentration and atomic configurations, using an hybrid DFT approach.




Contact: Rita Magri

email: magri -at- unimore.it

Title: Rational design of self-healing structures for the next-generation Li-ion batteries

ERC-SC: PE3 Condensed matter physics

Type: Theoretical/Computational

ABSTRACT

Batteries with very high energy densities, being at the same time inherently reliable and safe, will allow for electric vehicles travelling longer distances without polluting and will open to a multitude of future applications needed for the energy transition. The main idea is to insert smart functionalities into the battery, one of them is self-healing, SH. One way of implementing SH is to functionalize the anode and cathode surfaces using aptly designed polymers. For this thesis we are interested in cathode materials which are transition metal oxides. In this case SH has to be designed in order to protect the cathode surface against cracking due to the volume expansions and contractions, and against the loss of transition metal atoms. The rational design of the functionalized surfaces will be performed through the use of first-principles calculations to study the interaction between the cathode surfaces and the SH molecules in order to shed light on the SH action and on multiscale methods to simulate the battery behavior with and without self-healing polymers. The proposed work is part of an International Collaboration (BAT4EVER European Project) with possibility of interaction with international Laboratories providing material synthesis and characterization of the materials.

Notes: Si, progetto Europeo BAT4EVER



Contact: Rita Magri

email: magri -at- unimore.it

Title: Growth simulation of the GaN(0001) surface

ERC-SC: PE3 Condensed matter physics

Type: Theoretical/Computational

ABSTRACT

Control of growth front is of considerable interest for the engineering of material surfaces tuning them towards the desirable shape and function. In our group we have developed an original model to simulate the epitaxial growth of semiconductor surfaces and formation of nanostructures. This model uses among the input parameters some quantities which are difficult to determine experimentally. These parameters can be extracted from atomistic calculations, such as the calculations based on the ab-initio Density Functional Theory, of model surfaces. Of particular interest is the GaN(001) surface. Experimentalists have observed bunching on this surfaces for crystals doped with Si, at different miscut angles. The bunching seems to depend strongly on the growth rate and the temperature. The main step of this thesis work is to obtain using the DFT approach the Potential Energy Surface (PES) and from it derive the diffusion constants of Ga and N. This work is in collaboration with a group from Poland.

Notes: Ci sono possibilità di cooperazioni con gruppi sperimentali a livello internazionale.



Contact: Professor Ciro Cecconi

email: ccecconi -at- unimore.it

Title: Studying folding, misfolding and aggregation of proteins using optical tweezers

ERC-SC: PE3_19 Biophysics

Type: Experimental

ABSTRACT

Proteins must fold into compact and unique three dimensional structures to perform their specific functions. If folding goes wrong, proteins become useless and often toxic molecules for living cells. Millions of people all around the world suffer from diseases caused by protein misfolding, such as Alzheimer’s disease and Parkinson’s disease. Despite its importance, our understanding of the basic rules that govern the attainment of a protein structure is still incomplete. This lack of information is partly due to the inadequacy of conventional bulk methods to study a process that is highly heterogeneous. The advent of single-molecule

techniques, such as optical tweezers, has provided an innovative perspective on the protein folding problem, allowing us to go beyond the ensemble average measured by traditional techniques and dissect folding and misfolding mechanisms in unprecedented detail.

In our laboratories we use optical tweezers to explore the folding pathways of different proteins and elucidate the mechanisms by which certain environmental factors promote or inhibit their misfolding and aggregation. These studies are done in collaboration with internationally renowned scientists, such as Prof. S. Tans (http://tansgroup.amolf.nl/), Prof. B. Kragelund (http://www1.bio.ku.dk/english/research/bms/research/sbinlab/groups/bbk/) and Prof. S. Carra (http://personale.unimore.it/rubrica/dettaglio/carra)


Notes: It is not required to spend time abroad



Contact: Paolo Bordone

email: bordone -at- unimore.it

Title: Transport Properties of Continuous-Time Quantum Walks on Graphs in Presence of Environmental Noise

ERC-SC: PE3 Condensed matter physics

Type: Theoretical/Computational

ABSTRACT

Quantum walks are the quantum analogous of the classical random walks and describe the propagation of a quantum particle over a n-dimensional graph. Because of their quantum nature, which allows for quantum superposition of states and interference, quantum walks show a very different behavior compared to their classical counterparts. This behavior allows one to exploit quantum walks for tasks that cannot be achieved with the limited resources of classical random walks. For this reason, a lot of interest has arisen around quantum walks, especially because of their central role in non-deterministic algorithms, universal quantum computation, and in modeling processes in biological systems. Usually, in the literature, quantum walks are described in terms of the diffusion of particles over a perfect periodic potential, where it is assumed that no defects or disorder in the lattice enter the picture. However, in realistic physical implementation of quantum walks noise is always present, due to fabrication imperfections or by the inevitable interaction with the external environment which induces decoherence.

Our research group has recently approached the problem of transport of continuous-time quantum walks on graphs. The aim of the proposed thesis is to move a step forward including in the model the effect of dynamical disorder. The relative contributions of the interaction intensity and of the noise parameters on the dynamics effects will be investigated, as well as the transition between the quantum and the classical behavior. The study is performed using analytical (in particular resorting to the density matrix formalism) and numerical approaches.


Notes: no



Contact: Paolo Bordone

email: bordone -at- unimore.it

Title: Theory and Modeling of Flying Qubits Based on Co-propagating Edge Channels

ERC-SC: PE3 Condensed matter physics

Type: Theoretical/Computational

ABSTRACT

Quantum bits (or qubits) are the fundamental units of quantum computing. Recently, many methods of encoding flying qubits have been proposed, and one of the most promising is the use of copropagating edge states of different Landau levels, i.e. ballistic channels which arise in a magnetic field in the IQHE and which are characterized by large coherence lengths. This approach does not suffer from the topological problem of the traditional systems used in the literature, where the use of identical edge channels (of the same Landau level but separated in space) imposes strong limits in the scalability of the logic gates, which is a key requirement for quantum computing. Moreover, recent experimental advancement made single-electron sources available for solid-states devices: a result which opens new fascinating possibilities in the processing of the information encoded in a single carrier at a time. Our research group recently approached the coherent transport inside edge channels and developed some numerical codes and analytical methods to characterize the transport of localized carriers in solid-state single-particle logic gates (such as Mach-Zehnder interferometers). The goal of this master thesis is the characterization (via numerical simulations) of the interference process in electronic interferometer, used as logic gates, and realized through co-propagating edge channels, in which we inject electrons modelled with localized wavefunctions. Many key features – including the spread of the wavefunction, the energy selectivity of the scattering, the differences in the group velocities of the carriers – need to be explored in order to optimize the operating conditions of the device.

Notes: no



Contact: Sergio D'ADDATO

email: daddato -at- unimore.it

Title: Characterization of noble metal nanoparticles with photovoltaic applications

ERC-SC: PE3_12 Nanophysics

Type: Experimental

ABSTRACT

Noble metal nanoparticles (NPs) have shown new and interesting advanced properties compared to their bulk counterparts. Generally, NPs have established new technological applications in photovoltaics, magnetic recording, catalysis, medicine etc. A very interesting property of metal NP, like Ag, Au and Cu is the presence of surface plasmon resonance (SPR) in the UV-Vis spectrum. One of the most interesting applications of plasmonic NPs is their employment as light trapping materials in photovoltaic cells. We propose a thesis devoted to the investigation of noble metal NPs synthesized with a source which is able to produce and mass-selected clusters. The study will be focused on the structure and optical properties of the individual particles and of the nanoparticle assembled films. Some films will be grown on perovskite solar cells, in order to engineer the devices and reach an improvement in efficiency. The techniques to be used will be XPS, SEM, TEM and optical absorption and reflectivity.

Suppl.Mat.: https://drive.google.com/open?id=1K09ffV8Xx1j1GHfAC5dZRyt54bK0SMtL

Notes: It will also be possible to use HR-TEM and Synchrotron Radiation techniques, if available at the time of the thesis work.



Contact: Sergio D'ADDATO

email: daddato -at- unimore.it

Title: Characterization of noble metal nanoparticles with photovoltaic applications

ERC-SC: PE3_12 Nanophysics

Type: Experimental

ABSTRACT

Noble metal nanoparticles (NPs) have shown new and interesting advanced properties compared to their bulk counterparts. Generally, NPs have established new technological applications in photovoltaics, magnetic recording, catalysis, medicine etc. A very interesting property of metal NP, like Ag, Au and Cu is the presence of surface plasmon resonance (SPR) in the UV-Vis spectrum. One of the most interesting applications of plasmonic NPs is their employment as light trapping materials in photovoltaic cells. We propose a thesis devoted to the investigation of noble metal NPs synthesized with a source which is able to produce and mass-selected clusters. The study will be focused on the structure and optical properties of the individual particles and of the nanoparticle assembled films. Some films will be grown on perovskite solar cells, in order to engineer the devices and reach an improvement in efficiency. The techniques to be used will be XPS, SEM, TEM and optical absorption and reflectivity. It will also be possible to use HR-TEM and Synchrotron Radiation techniques, if available at the time of the thesis work.

Suppl.Mat.: https://drive.google.com/open?id=1fsb0Ffib03E-UBebN6Pv0dJqeAAjYB6Y



Contact: alberto.rota -at- unimore.it

email: rotal -at- unimore.it

Title: Functionalization of additive manufacturing materials

ERC-SC: PE3 Condensed matter physics

Type: Experimental

ABSTRACT

Additive manufacturing (AM) is a production technique based on a layer-by-layer fabrication strategy, also known as 3D printing. AM techniques provide interesting advantages with respect to conventional fabrication techniques due to their speed and high adaptability to complex geometrical requests, allowing just-in-time manufacturing, avoiding waste of space and of material. However, some drawbacks, such as surface finishing and bulk defects, are typical of these techniques. In order to overcome these aspects, the mechanical characteristics of AM surfaces can be improved with Hi-Tech coatings, which are able to improve the mechanical properties and reduce friction and wear.

The aim of this thesis is the fabrication and characterization of self-lubricant coatings (DLC, MoS2) on AD materials, in order to design new smart materials for mechanical applications. The coatings will be fabricated by means of magnetron-sputtering PVD. The tribo-mechanical properties will be estimated by tribometers and indenter, as well as their morphological and chemical properties.

The activity will be carried on in collaboration with private enterprises, being related to the RIMMEL industrial project, funded by Emilia Romagna region.




Contact: alberto.rota -at- unimore.it

email: rotal -at- unimore.it

Title: Tribological properties of MXene materials

ERC-SC: PE3 Condensed matter physics

Type: Experimental

ABSTRACT

MXene nano-sheets are a newly emerging class of a layered materials, composed of nitrides or carbides of early transition metals and derived by MAX-phases. By selectively removing the A-layers from the parental MAX-phase, MXene nano-sheets, with their most studied member Ti3C2Tx, can be synthesized. The TiC bulk phase is widely used in many fields of engineering due to their hardness, high melting point and high corrosion resistance, but generally suffers from poor tribological properties. In this context, MXene nano-sheets may help to overcome this short-coming due to the easy-to-shear ability between adjacent layers.

The proposed thesis aims at exploring the lubricating properties of MXene nano-sheets in different configurations (dry flakes, liquid suspension) as a function of humidity and of the lubricated support (steel, Fe, Cu).




Contact: alberto.rota -at- unimore.it

email: rotal -at- unimore.it

Title: Mechanical and friction properties of Graphene modulated by strain

ERC-SC: PE3_12 Nanophysics

Type: Experimental

ABSTRACT

Mechanical strains externally induced on 2D materials has been proved to strongly perturb the bands structure and so the electronic and photonic properties of these systems. Moreover, recent works proposed that also friction response may be modulated by strain or strain gradient fields.2D materials are typically supported by a substrate and interactions at the interface may produce specific strain fields. Understanding the mechanical properties 2D systems, i.e. the interface formed by the atomic layer and the supporting surface, is mandatory to optimize a broad range of functionalities, but it is also very interesting because of the intrinsic mechanical properties developed at these scale where vdW interactions play a fundamental role.

The proposed thesis aims at understanding mechanical and friction properties of single layer graphene subject to controlled strain. In particular, we will explore by Atomic Force Microscopy flat and nano-patterned regions of a SiO2 sample covered by graphene. This is a prototypical system where the conformation of graphene sheet to the nano-structured areas produces regions with variable strain.




Contact: Guido Goldoni

email: ggoldoni -at- unimore.it

Title: Electronic states in hetero-structured semiconductor nanowires

ERC-SC: PE3_5 Electronic properties of materials and transport

Type: Theoretical/Computational

ABSTRACT

Which solid state system is most suited to implement a new generation of scalable quantum computers? The response is likely to lie in some type of nano-material. Nano-wires are quantum materials in the form of a quasi-one-dimensional crystal which hold promises both for future quantum technologies as well as for many, more traditional nano-technologies, from sensing devices to energy harvesting.


In this thesis we study the electronic states of nanowires which are made out of layers of several materials, which alternate radially. These so-called core-shell nanowires are the platform for a number of applications, as well as hosting intriguing fundamental phenomena, such as topologically protected states -the so-called Majorana zero modes- which could be used to code quantum information.


The thesis will focus on the electronic and/or spin excitations of multilayer nanowires and the prediction of their transport or spectroscopic signatures.

In simulating the electronic states of core-shell nanowires, as these systems are named, the student will get familiar with state-of-the-art modelling of semiconductor quantum materials.


The activity has a theoretical-computational character, making use of in-house developed software. Depending on the student’s background and interests, the argument may be developed on a more formal or computational side, possibly including the development of high-performance software.


Notes: This activity will enjoy collaboration with experimental leading groups which grow and characterize the same class of nano-materials.



Contact: Marco Gibertini

email: gibertini -at- unimore.it

Title: Modelling dielectric screening in two-dimensional materials

ERC-SC: PE3 Condensed matter physics

Type: Theoretical/Computational

ABSTRACT

Owing to their ultimate atomic thickness, two-dimensional materials have a peculiar dielectric response to external potentials. In this project the student will develop simple models to describe such peculiar behavior of monolayers. Possible approaches might range from the development of approximations to the full density-density response function to simplified descriptions in terms of idealized effective media. Analytical work might be combined with numerical calculations and even first-principles density-functional theory simulations.

Notes: In collaboration with Thibault Sohier at the University of Liege, Belgium



Contact: Marco Gibertini

email: gibertini -at- unimore.it

Title: Effective Fröhlich interaction in 2D semiconductors

ERC-SC: PE3 Condensed matter physics

Type: Theoretical/Computational

ABSTRACT

Lattice vibrations can generate long-range electrostatic potentials that hinder the motion of electrons in solids. One example is the Fröhlich interaction with polar longitudinal optical phonons. In this project the student will improve existing models to describe this interaction in terms of few parameters, including in particular the subtle effects associated with the finite thickness of two-dimensional materials.

Notes: In collaboration with Thibault Sohier at the University of Liege, Belgium



Contact: Marco Gibertini

email: gibertini -at- unimore.it

Title: Accelerating the calculation of Raman tensors using symmetry

ERC-SC: PE3 Condensed matter physics

Type: Theoretical/Computational

ABSTRACT

The Raman tensor gives the intensity and polarization dependence of the inelastic scattering of radiation associated with lattice vibrations in a solid or molecule. Within the Placzek approximation, the Raman tensor associated with a given phonon can be expressed in terms of the derivatives of the electric polarizability tensor with respect to atomic coordinates. A finite difference approach would thus require at least 3N evaluations of the electric polarizability, which is very time consuming. In this project the student will exploit symmetry arguments to reduce the number of calculations to be performed and will implement the approach in the open-source python code Phonopy.

Notes: : Previous knowledge of the Python programming language is strongly suggested. Possible collaborations with Prof. Atsushi Togo (NIMS, Japan)



Contact: Marco Gibertini

email: gibertini -at- unimore.it

Title: Prediction of the ultra-low frequency Raman spectrum of all layered materials

ERC-SC: PE3 Condensed matter physics

Type: Theoretical/Computational

ABSTRACT

Low-frequency vibrations in layered materials involve the rigid motion of the layers and are typically classified as shear and breathing modes. Recent developments in Raman spectroscopy now allows to probe these modes and the corresponding spectra strongly depend on the number of layers, both in terms of frequencies and intensities. While automatic approaches to predict the mode frequencies and optical activity exist (https://www.materialscloud.org/work/tools/layer-raman-ir), we are still missing a simple strategy to predict the layer-number dependence of the Raman intensity. In this project the student will develop such automated algorithms using symmetry arguments, and implement them in a python code with a corresponding graphical interface.

Notes: Previous knowledge of the Python programming language is strongly suggested. Possible collaborations with Dr Giovanni Pizzi and Prof Nicola Marzari (EPFL, Switzerland)



Contact: Marco Gibertini

email: gibertini -at- unimore.it

Title: Topological van der Waals heterostructures from first principles

ERC-SC: PE3 Condensed matter physics

Type: Theoretical/Computational

ABSTRACT

Topological materials display properties that robust against disorder and other perturbations. In two dimensions topological materials are rare and new strategies are needed to artificially create topological materials. A possible scenario arises from stacking together two “trivial” materials to create a so-called van der Waals heterostructure that displays topological order. In this project the student will investigate possible realizations of such artificial topological materials using first-principles density-functional theory simulations.



Contact: Paola Luche, Sergio D'ADDATO

email: daddato -at- unimore.it

Title: Oxides combined with plasmonic nanoparticles for efficient solar energy conversion

ERC-SC: PE3_12 Nanophysics

Type: Experimental

ABSTRACT

Research on materials for efficient solar energy conversion is very important in order to face present environmental and climate emergencies. Oxides combined with specific metal nanoparticles allow to efficiently convert solar light into chemical or electric energy by exploiting the excitation of localized surface plasmon resonances and the energy/charge transfer to the neighboring oxide. The activity foresees the growth of nanoparticles of Ag, Au, Cu and corresponding alloys combined with oxides (CeO2, Cu2O, Fe2O3), and in the morphological (STM/AFM, SEM, TEM), electronic (XPS, UPS) and optical (UV-Vis) characterization.

Notes: The most promising samples will be also studies using time-resolved spectroscopies (FTAS, TR-XAS) at shared facilities (EFSL Rome; FERMI/ELETTRA Trieste) to have information on the mechanisms for energy/charge transfer.



Contact: Rossella Brunetti (rossella.brunetti -at- unimore.it)

email: brunetti -at- unimore.it

Title: Charge transport models for amorphous and crystalline chalcogenides to explore the physics of Phase-Change Memory (PCM) devices

ERC-SC: PE3_5 Electronic properties of materials and transport

Type: Theoretical/Computational

ABSTRACT

PCM is the most mature among the various kinds of emerging memories, intensively explored in the last twenty years for embedded non-volatile memory (eNVM) applications, because of its advantages over conventional eNVMs [1]. Its manufacturability and reliability have been demonstrated on high density standalone memories. Among the many innovations foreseen for this class of memories, as an example we quote that Embedded PCMs (ePCMs) have the potential to become the mainstream eNVM technology at 28 nm and below for automotive grade applications thanks to their single-bit alterability, which is a key enabler for a much simpler data handling with respect to Flash-based memories, and their reliability properties, which have been confirmed even in the temperature range required for automotive applications by European leader Companies in the NVM market [2].

In standard architectures, non-volatility is achieved by means of Flash memories, that store information by confining carriers between suitable energy barriers; the stored charge modifies the threshold voltage of an MOS transistor. However, the International Roadmap for Devices and Systems and the integrated-circuit manufacturers express concerns about the possibility of safely scaling a memory chip below the 10nm range without revolutionizing the storage mechanism, architecture, materials, and fabrication process. Moreover, no significant cuts in energy consumption are likely to occur with the present technology.

The advances in NVM technology made in the last ten years by research institutions and industries brought about alternative NVM concepts to overcome these limits. The most studied candidates for next-generation NVM are two-terminal devices with a capacitor or a resistor as storage element [2]. The memory effect of these devices is associated with a functional property, like, e.g., the electrical resistivity or the optical reflectivity. Using two- instead of three-terminal devices is attractive for manufacturers, as this approach simplifies memory layout, and allows achieving a very dense storage capability in the back-end-of-line (BEOL) of CMOS process flow.


A class of alloys including elements of the VI-A group, called chalcogenides, can easily and reversibly be switched between the amorphous and the crystalline phase upon the application of a heat source, like a laser spot or an electric current. Despite the intrinsic thermodynamic instability common to all glasses, the amorphous phase requires up to some years to spontaneously recrystallize at room temperature so that the amorphous state is considered stable as well in any practical application. On the contrary, crystallization becomes very rapid when the material is heated above the crystallization (or the glass transition) temperature.

Moreover, the amorphous and the crystalline phases exhibit in general a very large contrast in reflectivity and resistivity. These features make chalcogenide layers as the key component of a non-volatile PCM, which is basically a thin-film resistor whose low-field resistance varies by at least two orders of magnitude depending on the phase state of the active region.

The knowledge of the optical and electrical properties of chalcogenide materials is of the utmost importance for unraveling the physics of the switching and their behavior in an NVM device. Some of these properties are often derived, either directly or indirectly, from optical experiments on thin films. Most of the results disclosed in the literature have been determined for the Ge2Sb2Te5 (also known as GST-225) and for the GeTe alloys, which are prototypical chalcogenides. A suitable customization of the ternary GST alloy has been demonstrated to achieve PCM devices well-fitting the standards of automotive microcontrollers as for retention, commutation speed and programming currents.


Depending on the phase of the chalcogenide layer, two distinct current vs. voltage characteristics are found. The crystalline phase is basically a simple resistor. The amorphous phase features, instead, a highly non-linear, S-shaped characteristic: by increasing the applied voltage the electric current spans a high resistive branch at the lowest voltages and, when a suitable threshold voltage is reached, a sudden current increase takes place, still within the amorphous phase, and a low resistive branch at high bias is reached (Ovonic Threshold Switch, OTS). The latter electric response eventually merges with the characteristic of the crystalline phase (Memory Switch, MS). By suitably exploiting the above-described electrical properties, chalcogenides can be used to design both the memory element and its selector.


The proponent research group has been working on theoretical and computational models for charge transport in amorphous and crystalline chalcogenides since about 20 years, in collaboration with national groups active in the field of device simulation and with academic experimental and R&D groups worldwide [3,4]. A research project has been recently submitted to the national PRIN2020 contest and it is presently under evaluation [5].


The research proposal for a Master thesis deals with the challenge of modeling the phase transition process into the state-of-the-art hydrodynamic model included into the present simulation tools. Only the transport features of the amorphous phase are described so far, i.e., only the OTS effect can be described. The inclusion of both OTS and MS description into the theoretical model and its numerical implementation is a necessary step towards a multi-purpose physics-based PCM device simulation tool to be used in many emerging applications, included in the focus of the European Horizon2020 Project and in the area of interest of leader semiconductor Industries worldwide.


[1] E. Piccinini and C. Jacoboni: “Phase-change memories” in Springer Handbook of Semiconductor devices, R. Brunetti, S. Reggiani, and M. Rudan Eds., Springer 2021 (in press).

[2] P. Cappelletti, R. Annunziata, F. Arnaud, F. Disegni, A. Maurelli, ad P. Zuliani, Phase change memory for automotive grade embedded NVM applications, J. Phys. D, Appl. Phys. 53, 193002-011 (2020).

[3] R. Brunetti, C. Jacoboni, E. Piccinini, M. Rudan: Band transport and localised states in modelling the electric switching of chalcogenide materials, J. Comp. Elect. 18, 1–9 (2019).

[4] R. Brunetti and M. Rudan: “Transport models for amorphous semiconductors”, in Springer Handbook of Semiconductor devices, Brunetti, Reggiani, Rudan Eds., Springer 2021 (in press).

[5] Project GRAphene-contacted PHase-change memory for INnovative Controllers in Automotive applications. Partners: Dipartimento dell’energia Elettrica e dell’Informazione Marconi UniBo, Dipartimento di Fisica, Informatica e Matematica UniMoRe, Institute for Microelectronics and Microsystems (IMM) CNR-Bo, Dipartimento di Ingegneria Industriale e dell’Informazione UniPv.




Contact: Andrea Bizzeti

email: andrea.bizzeti.gmail -at- unimore.it

Title: Rare decays of strange particles with LHCb

ERC-SC: PE2 Fundamental constituents of matter

Type: Experimental

ABSTRACT

The LHC accelerator at CERN is presently the most powerful available factory of strange particles. Thanks to its excellent particle identification capabilities, the LHCb experiment is the ideal tool to search for dynamics beyond the Standard Model of Particle Physics in exclusive rare decays of strange hadrons. Using the data collected during the past years, we will perform a preliminary study of the LHCb potential to detect the decay of the Ks meson to four leptons, a mode particularly sensitive to possible new physics contributions.

Notes: LHCb international collaboration



Contact: marco.affronte -at- unimore.it

email: affronte -at- unimore.it

Title: Development of quantum detectors for the search of faint signals.

ERC-SC: PE3_12 Nanophysics

Type: Experimental

ABSTRACT

Due to their small energy, the detection of microwave photons is an intriguing fundamental and technological challenge. It is currently a central issue in experiments dedicated to the search of dark matter particles [1] as well as for the measurement of cosmic microwave background [2]. Nano-detectors based on superconducting devices [3] or semiconducting nanowires [4] are current technology used to detect faint microwave signals. This project aims at the realization and characterization of a prototype of one of these detectors in collaboration with (inter)national laboratories. Advanced lithographic techniques ( eg. Electron Beam Lithography) will be used for the realization three terminal detectors based on semiconucor nanowires [5] while measurements at very low temperature will be performed for characterization of the devices. The proposed thesis work will focus on one of these tasks and includes participation to a large scale experiments [ such as https://supergalax.eu/ ] for search of faint signals.


[1] Phys. Dark Univ. 12, 37 (2016).

[2] Ann. Rev. of Astronomy and Astrophysics 54, 227-269 (2016);

[3] J. of Appl. Phys. 128, 044508 (2020); J. Low Temp Phys 199, 1107 (2020) and ibidem p. 891.

[4] Sensors 2020, 20, 4010; https://doi.org/10.3390/s20144010

[5] Sci. Rep. 9, 19523 (2019)


Notes: https://supergalax.eu/



Contact: marco.affronte -at- unimore.it

email: affronte -at- unimore.it

Title: Quantum Technologies for advanced Magnetic Resonance.

ERC-SC: PE2_10

Type: Experimental

ABSTRACT

Electron spins can be coupled to microwave photons and coherently manipulated by microwave pulses. The Physics and technology behind this is a central problem in Quantum ElectroDynamics (QED). It is similar to that used for superconducting Josephson devices and eventually allows the encoding of quantum bits (qubits) or pulse sequences suitable for quantum sensing [2]. Molecular spins provide a wide palette of spin qubits thanks to their long coherence time [3]. Here we focus on the use of QED techniques to enhance sensitivity of magnetic resonance. More specifically, the thesis work will consist in: i) developing a microwave planar resonator on a superconducting chip; ii) learning and using advanced microwave techniques including heterodyne setup for pulsed microwave measurements [4]; iii) optimizing and testing sequences of microwave pulses for the measurement of characteristic relaxation times of molecular spins. The development of microwave pulse technology will be carry out in collaboration with an industry and Karlsruhe Institute for Nanotechnologies.

[1] Haroche, Reimand “Exploring the Quantum”, Oxford press.

[2] Towards Quantum Sensing with Molecular Spins F. Troiani, A. Ghirri, M. G. A. Paris , C. Bonizzoni, M. Affronte, Journal of Magnetism and Magnetic Materials 491 (2019) 165534; https://doi.org/10.1016/j.jmmm.2019.165534

[3] Molecular Spins in the Context of Quantum Technologies A. Ghirri, A. Candini, M. Affronte Magnetochemistry 3(1), 12, (2017) https://www.mdpi.com/2312-7481/3/1/12

[4] Storage and retrieval of microwave pulses with Molecular Spin Ensembles C. Bonizzoni, A. Ghirri, F. Santanni, M. Atzori, L. Sorace, R. Sessoli, and M. Affronte NPJ Quantum Information (2020)6: 68 ; https://doi.org/10.1038/s41534-020-00296-9


Notes: Karlsruhe Institute for Nanotechnologies.



Contact: Stefania Benedetti, Sergio D'Addato

email: daddato -at- unimore.it

Title: Growth and control of refractory materials for plasmonics

ERC-SC: PE3_5 Electronic properties of materials and transport

Type: Experimental

ABSTRACT

Recently the development of materials for plasmonic applications (like photocatalysis, optoelectronics, thermoplasmonics, etc) are moving to alternative refractory compounds other than noble metals, more resistant to extreme conditions and less expensive. The proposed activity aims at the growth and study of several of these possible materials, like oxides (Al:ZnO, Nb:TiO2) and nitrides (TiN, ZrN) to control their optical and electronic response in selected spectral ranges for films, nanostructures or simple devices. These materials will be prepared by reactive sputter deposition and analyzed by means of several state-of-the-art techniques (XPS, SEM, XRD, Hall measurements, AFM, optical spectrometry) present at the Physics Department in collaboration with CNR-NANO.

Notes: The activity foresees the use of shared facilities like ESFL and/or ELETTRA-NFFA. The possibility to directly take part to the experiments at the facilities will be evaluated depending on the travel restrictions.



Contact: Paola Luches, Sergio D'Addato

email: daddato -at- unimore.it

Title: Oxides combined with plasmonic nanoparticles for efficient solar energy conversion

ERC-SC: PE3_12 Nanophysics

Type: Experimental

ABSTRACT

Research on materials for efficient solar energy conversion is very important in order to face present environmental and climate emergencies. Oxides combined with specific metal nanoparticles allow to efficiently convert solar light into chemical or electric energy by exploiting the excitation of localized surface plasmon resonances and the energy/charge transfer to the neighboring oxide. The activity foresees the growth of nanoparticles of Ag, Au, Cu and corresponding alloys combined with oxides (CeO2, Cu2O, Fe2O3), and in the morphological (STM/AFM, SEM, TEM), electronic (XPS, UPS) and optical (UV-Vis) characterization. The most promising samples will be also studies using time-resolved spectroscopies (FTAS, TR-XAS) at shared facilities (EFSL Rome; FERMI/ELETTRA Trieste) to have information on the mechanisms for energy/charge transfer.

Notes: The activity foresees the use of shared facilities like ESFL and/or FERMI-ELETTRA. The possibility to directly take part to the experiments at the facilities will be evaluated depending on the travel restrictions.



Contact: Giorgia Brancolini

email: giorgia -at- unimore.it

Title: "Atomistic Simulations of Gold Surfaces Functionalization for Nanoscale Biosensors Applications"

ERC-SC: PE3_19 Biophysics

Type: Theoretical/Computational

ABSTRACT

The thesis involves the development of computational protocol to model sensors at the level of single molecular interactions, and for optimizing the physical properties of surface conjugated ligand which is crucial to enhance output of the sensor. The work will require to learn and apply state-of-the-art atomistic simulations of metal surfaces functionalized with different chemical groups interacting with a series of proteins analytes, followed by a direct comparison with available experimental data. The work include the possibility to collaborate with the group of Marco Cecchini at NEST, Scuola Normale Superiore, Pisa, Italy



Contact: Giorgia Brancolini

email: giorgia -at- unimore.it

Title: Computational Design of a Mutation-Independent FRET sensors to Assess Coronavirus Titre

ERC-SC: PE3_19 Biophysics

Type: Theoretical/Computational

ABSTRACT

Atomistic simulations and computational molecular analyses will be employed to develop a FRET sensor to assess the presence of Coronaviruses, using a more direct, rapid and reliable way than currently available protocols. Fluorescence resonant energy transfer (FRET) exploits the non-radiant dipole-dipole transfer of energy between two spectrally overlapping fluorophores that are in close proximity (donor, D, and acceptor, A) to capture the molecular interactions that occur at nanometer level.

Strategies will combine modeling (in silico) with laboratory testing (in vitro).

Notes: A collaboration with experimental groups at the University of Pisa is foreseen.



Contact: Mauro Ferrario

email: ferrario -at- unimore.it

Title: Driving mass transport in electrolyte solution by NEMD

ERC-SC: PE3_1 Structure of solids and liquids

Type: Theoretical/Computational

ABSTRACT

By applying thermodynamic perturbations within a non equilibrium molecular dynamics scheme selective mass transport can be activated in electrolyte solution in model confined conditions. This will allow to study the microscopic mechanisms underlying physical phenomena of interest in a variety of different fields like for example the role of the depolarization of concentration gradients in biological system signalling.

Notes: Collaboration possible with groups abroad.