Zurich, Zurich, Switzerland
Solid-state physicist with a Ph.D. in materials science and engineering, I'll bring to your company more than 7 years of experience in materials development, quantum optics, and high-resolution optical and electron microscopy. During my Ph.D. at École Polytechnique Fédérale de Lausanne (EFPL), Switzerland, I characterized and engineered single-photon emitters in semiconductor nanostructures to match the light absorption by Rb atoms: to achieve this goal, I combined materials design, strain tuning, and the correlation of optoelectronic functionality with materials crystal structure control. I master the union of optical and electron microscopy in cathodoluminescence. During my postdoc training at Lawrence Berkeley National Lab (LBNL), USA, I built on my expertise and pushed forward the application of this technique to 2D materials. I am fascinated by questions revolving around understanding, imaging, and controlling quantum phenomena and optoelectronic properties of semiconductors at the nanoscale. I thrive in an international environment and I am excited to discuss these topics with scientific collaborators and customers worldwide to find innovative solutions to challenging applications. Email: [email protected] Publications: https://www.researchgate.net/profile/Luca-Francaviglia/research
Structural & functional analysis of photonic-engine materials
High-resolution imaging & spectroscopy of the optical response of 2D semiconductors. Scientific advisors: Dr. Frank Ogletree, Dr. Alexander Weber-Bargioni, and Dr. Archana Raja at the Imaging and Manipulation of Nanostructures Facility of the Molecular Foundry at Lawrence Berkeley National Lab (LBNL). First joined the Facility with a Swiss National Science Foundation (SNSF) Early PostDoc Mobility fellowship (1.5 years). Main achievements: - First measurement of the charge-carrier diffusion length in hexagonal boron nitride by an innovative cathodoluminescence design that I designed and implemented to bypass the challenges of optical measurements with wide-bandgap materials. - I defined an experiment- and simulation-based metric to set the achievable limits of brightness and resolution (down to ~30 nm) of cathodoluminescence of monolayers of 2D semiconductors buried in hexagonal boron nitride as guidelines for future users of this technique. Main tasks: - Plan & implement research projects - Cathodoluminescence, micro-photoluminescence, and micro-Raman spectroscopy and mapping at room temperature and in a liquid-helium cold-finger cryostat (Janis) - CAD and operation of optomechanical units based on piezoelectric manipulators for in-situ micropositioning of optical fibers in a cathodoluminescence microscope - Data acquisition, analysis, and visualization (LabView, Python, Origin) - Chemical Vapor Deposition of WS2 and thermal annealing - Publication of research articles in peer-reviewed journals - Presentations at international conferences - Co-supervision of students
Thesis: “Mechanisms shifting the emission energy of self-assembled quantum dots in nanowires” Supervisor: Prof. Anna Fontcuberta i Morral at Laboratory of Semiconductor Materials (LMSC), École Polytechnique Fédérale de Lausanne (EPFL). Main achievements: - Energy shift up to 300 meV of quantum-dot single-photon emitters grown by molecular beam epitaxy; consequent energy matching with a cell of Rb atoms as quantum repeater - Demonstrated liquid-helium-temperature single-photon emission by hybrid free-space and fiber-coupled SPAD-based HBT g2 on newly material engineered nanowires. - Controlled the energy and intensity of the single-photon emission of nanowire quantum dots by a straining oxide envelope deposited by CVD. - Demonstrated the correlation of the crystal structure with the occurrence and emission energy of quantum dots in nanowires by complementary transmission electron microscopy and microphotoluminescence and cathodoluminescence at 4K. Main tasks - Plan & implement research projects, design & conduct experiments. - Writing molecular beam epitaxy recipes for nanowire growth - Developed user protocol, manual, and documentation and trained 10+ internal and external users on a 1 milion CHF Attolight cathodoluminescence microscope at the Interdisciplinary Centre for Electron Microscopy (CIME) - Mentored and trained 5+ students and several collaborators on optical setups and electron microscopes at the Laboratory of Semiconductor Materials (LMSC) - Data acquisition, analysis, and visualization (LabView, Matlab, Mathematica, Origin) - Simulation of semiconductor optoelectronic properties (Nextnano) - Independent experimental work and design, and proactive contribution to international collaborations leading to a book contribution and peer-reviewed article publications. - Organized the “NCCR QSIT Junior meeting 2017” (3 days, 36 participants)
Project: “Optical coupling between quantum dots in nanowires and Rb atoms” Advisors: Prof. Richard Warburton and Prof. Anna Fontcuberta i Morral Main achievement: - Proved energy-tuning and match between nanowire-quantum-dot emission and a cell of hot Rb atoms Main tasks: - Resonant photoluminescence of single-photon emitters in nanowires in liquid-helium immersion cryostat - Measurement of the absorption of the nanowire emission by a cell of Rb atoms