Proposte Tesi - Condensed Matter Physics and Photonics
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Area
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Titolo | Abstract | Contatto |
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| Quantum information theory | Analysis of quantum key distribution |
The security of the internet relies on distributing and managing secret keys. Modern cryptography generates keys that are secure conditional to the promise that some mathematical problem (such as factoring a large number) is hard to solve. This promise can be broken by more powerful supercomputers and quantum computers. Quantum key distribution (QKD) offers a solution to this security problem as it allows us to distribute unconditionally secure keys among distant users. The student will acquire the theoretical and mathematical tools to quantify the secrecy of a bit string and analyse a novel protocol for QKD based on coherent states of light. Further reading: |
cosmo.lupo@poliba.it |
| Quantum information theory | Measuring quantum randomness |
Measurements in quantum mechanics exhibit an intrinsic randomness that cannot be associated to lack of knowledge about the physical system. It has been proposed to use this phenomenon to build a "quantum random generator". The student will acquire the theoretical and mathematical tools to quantify randomness from physical systems, and use these tools to analyse a novel design for a quantum random number generator based on optical measurements of entangled states.
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cosmo.lupo@poliba.it |
| Quantum information theory | Sub-wavelength resolution from quantum imaging |
Ghost imaging exploits quantum or classical correlations to create an image of an object using the coincidences between pairs of photon detection events. In a standard set up, two correlated photons are generated. The first photon is scattered by the target object, and is then detected by a bucket detector. A bucket detector only reveals the presence of the photon, without spatial resolution. The second photon, which never interacts with the object, is instead focused on an array of detectors, which yield 2D spatial resolution. A diffraction-limited image is obtained by processing the data collected in correspondence of coincidence events. The student will explore the ultimate resolution of ghost imaging and the possibility of achieving resolution beyond the diffraction limit. Further reading:
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cosmo.lupo@poliba.it |
| Ultrafast laser microprocessing | Development of a smart procedure for the rapid prototyping of a polymeric lab-on-chip by femtosecond laser technology | L’attività di tesi prevede lo sviluppo di un lab-on chip polimerico per applicazioni biomedicali interamente realizzato con laser al femtosecondo. La fase di fabbricazione sarà seguita da una fase di caratterizzazione microfluidica del dispositivo | annalisa.volpe@uniba.it |
| Laser Spectroscopy | Tunable laser absorption spectroscopy exploiting a quartz tuning fork as optical detector | A quartz tuning fork (QTF) can be used as light detector exploiting light-induced thermo-elastic effect occurring within the quartz crystal. When the radiation hits the surface of the QTF, photothermal energy is generated because of light absorption by the quartz. Due to the thermo-elastic conversion, elastic deformations put prongs into vibration if the laser is intensity-modulated at one of the QTF resonance frequencies. Mechanical vibrations induce local strain and charges are generated via inverse piezoelectric effect. Thus, the QTF acts as a photodetector. This project aims to realize a gas sensor based on direct absorption spectroscopy in wavelength modulation and a QTF as optical detector. The light transmitted by a gas cell will be focused on the QTF surface where the maximum strain occurs. The photogenerated signal will be studied as a function of operating conditions, namely the laser spot position, the light intensity and the ambient conditions of the QTF. With the best conditions, the sensor transfer function as well as its sensitivity will be determined by a calibration procedure. Then, the ultimate detection limit and the normalized noise equivalent absorption will be evaluated. | pietro.patimisco@uniba.it |
| Data Analysis | Development of partial least squares regression tool for complex gas mixtures analysis in quartz-enhanced photoacoustic spectroscopy | Multivariate analysis (MVA) is a well-established tool to investigate physical systems made up of several components. Among different MVA methods, partial least squares regression (PLSR) stands out for its ability to deal with correlated and noisy experimental data. In optical gas sensing, measurement of single component concentration in a multi-component mixture is a crucial issue when several absorbing gases can compete one each other. For gas samples containing different absorbers species, spectral features belonging to different gas targets can overlap, requiring appropriate tools to identify and isolate each single component. The project aims to combine the quartz-enhanced photoacoustic spectroscopy (QEPAS) with PLSR to identify gas components in a mixture with strongly overlapping absorption features over the full spectral dynamic range of a laser source. An algorithm based on PLSR will be developed to retrieve absolute concentrations of gas components in the mixture. Then, the algorithm will be tested with a QEPAS sensor for spectroscopic analysis of complex gas mixtures. The ultimate precision and accuracy will be compared with standard MLR approach. | angelo.sampaolo@poliba.it |
| Condensed matter physics, surface properties | Work function imaging and modification | The knowledge of work function, i.e. the difference W between the Fermi energy and the vacuum level, is fundamental to understand the physics of surfaces, quantum structures and bio-sensor devices with sensitivity to the physical limit of single molecule [https://www.nature.com/articles/s41467-018-05235-z]. The thesis aims at assessing the local value of W and its modification as a function of the exposure of metallic gate surfaces to molecular interactions. Main thesis activities: i) deposition and photo-lithographic patterning of Au(111) nm-thick films by e-beam evaporation; iii) modification of the local work function using self-assembled monolayers. i) imaging with nm-resolution of the surface morphology and the local work function by Kelvin probe atomic force microscopy (KP-AFM). Main achieved expertise: nanoscopic device physics; clean room; AFM; high resolution image analysis; surface potential modeling; SEM characterization. | gaetano.scamarcio@uniba.it |
| Condensed matter physics, nano-photonics | Surface-enhanced and polarization-modulation infrared spectroscopy | Radiation–matter interaction in ultrathin monolayers deposited on nanostructured metal surfaces is strongly amplified by surface plasmon resonances and polarization modulation. In this way, the rich vibrational spectra of molecular films become measurable, allowing the assessment of the local molecular bonding structure and dipole orientation. Main thesis activities: i) modeling of the near-field evanescent wave propagation and radiation-matter-interaction in layered ultra-thin films; ii) set-up of in-situ surface-enhanced IR spectroscopy; iii) study of of the vibrational spectra of ultrathin films and correlation with their molecular structure. Main achieved expertise: nano-photonics; surface design and modification; Fourier-transform IR spectroscopy; radiation-matter modeling at the nanoscale. | gaetano.scamarcio@uniba.it |
| Condensed matter physics, nano-sensor devices | In-situ and operando force-volume atomic force microscopy | In electrolyte-based devices, like electrolyte-gated transistor sensors, the charge double layer (1-100 nm) that is formed close to electrode surfaces plays a central role in the signal transduction associated with molecular binding and sensing phenomena. Atomic force microscopy (AFM) in the force-volume mode allows to measure the ionic charge distribution with sub-nm resolution and monitor the electrostatic modifications induced by binding events. Main thesis activities: i) surface modification and characterization; ii) setting-up AFM in liquids; iii) measuring and modeling force-volume curves. Main achieved expertise: advanced AFM; surface design and modification. | |
| Condensed matter physics, optical spectroscopy | In-situ and operando micro-Raman scattering in graphene based devices | The electron-phonon interaction in graphene is strongly influenced by the relative level between the charge neutrality point and the Fermi energy. The latter shifts as a function of the applied electric field, causing a strong shift in the Raman-active peak frequencies. This effect can be used to sense local changes in the dipole structure in capacitive coupled electrolytic devices. Main thesis activities: i) fabrication of graphene based devices; ii) acquisition of micro-probe Raman spectra and Raman imaging maps as a function of the applied electric field; iii) analysis of Raman spectra. Main achieved expertise: graphene physics; micro-Raman spectroscopy and imaging; spectral analysis; SEM characterization; C-V characterization | gaetano.scamarcio@uniba.it |
| Condensed matter physics, nano-plasmonic sensors | Fabrication and characterization of gold nanostructures for optical sensing |
The localized surface plasmon resonance (LSPR) effect is based on the collective oscillation of electrons on the surface of nanostructures induced by visible light. This effect offers promising opportunities in sensing applications (dx.doi.org/10.1021/ac301825a) because of the high sensitivity to local changes in the refractive index and reduced cross-sensitivity to bulk properties. This effect can be used to capture the presence of relevant molecules in a sensing device. Main thesis activities: i) fabrication of the nanomaterial; ii) characterization of the nanomaterial; iii) application in the detection of relevant targets. Main achieved expertise: plasmonics; nanofabrication; clean room; AFM; high resolution image analysis; SEM; sensing application of the nanomaterial. |
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| Condensed matter physics, surface-molecule interaction | Single-molecule imaging to identify changes in the structural conformation of biomolecules |
Atomic Force Microscopy (AFM) is a powerful technique to image single molecules at the nanoscale without any laborious treatment or labelling. Therefore, it can be used to capture morphological and mechanical changes in the structure of biomolecules due to different external stresses. Main thesis activities: i) single biomolecule imaging (DNA, protein); ii) characterization of the mechanical properties of the biomolecule; iii) imaging and conformational analysis of the biomolecule. Main achieved expertise: advanced AFM; surface physical and chemical properties; clean room. |
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| Quantum Optical Technologies | Correlation Plenoptic Imaging, from foundations to applications | L’imaging plenottico in correlazione (CPI) è una nuova modalità di imaging quantistico che consente di rifocalizzare, a posteriori, fotografie sfocate e di ricostruire l’immagine tridimensionale di una scena, offrendo una combinazione di risoluzione e di profondità di campo senza precedenti. La tecnica trova applicazione in svariati contesti, dalla microscopia all’ispezione industriale, dal target detection all’imaging dallo spazio. Le proposte di tesi di laurea sono incentrate su attività sia sperimentali sia teoriche. In particolare, sono disponibili progetti di tesi con carattere
di fisica fondamentale (CPI con fotoni entangled, CPI in presenza di scattering e turbolenza, CPI con sorgenti a bassa coerenza, studio del rumore nei dispositivi di CPI, CPI con sensori a singolo fotone, imaging quantistico nel regime dei raggi X, ecc.) e di fisica applicata (costruzione e caratterizzazione di prototipi di CPI per microscopia, imaging iperspettrale, ispezione industriale, imaging dello spazio, imaging per esperimenti di fisica delle particelle, ecc.). L’attività di ricerca è condotta in collaborazione con università e centri di ricerca internazionali (EPFL, Università di Olomouc, INRIM, CNR, INFN, ecc.) e con aziende interessate allo sviluppo di dispositivi per imaging quantistico (Planetek, Leonardo, ecc.). Il lavoro di tesi si svolge in stretta interazione con dottorandi, assegnisti e giovani ricercatori del gruppo di ricerca locale. Le attività svolte per la tesi costituiscono in molti casi la base per pubblicazioni scientifiche su riviste internazionali e, in casi specifici, per la presentazione di una domanda di brevetto.
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Contatti: |
| Photonics: Laser Material Processing and lighting solutions for automotive | Analysis of the microdrilling process with bursts of femtosecond laser pulses with special polarization |
Processing of microholes and micropores has a key role in several application fields, from biomedicine to automotive. The quality of the microfeatures is one of the most critical requirements and is still a challenge for several processing technologies. This thesis project aims at developing an effective strategy based on ultrafast laser processing for fabricating matrices of micro-holes with reduced taper angle and high rounded shape, by exploting a novel irradiation technique together with a special polarization approach. The optical performances of the manufactured samples will be carried out in strict collaboration with the R&D department of Ferrari. Duration: min 3 months |
Contatto Uniba/CNR:
Contatto Ferrari: |