Postdoctoral Fellows

Fritz London Postdoctoral Fellows:

The Fritz London Postdoctoral Fellowship was established by an anonymous donor to honor the accomplishments of promising rising stars in the field of experimental condensed matter physics and to honor the impact of Prof. Fritz London’s accomplishments as a professor of physics and chemistry at Duke. Click here to read some of Prof. London’s history.

2016:

Andrew Traverso: I completed my Ph.D. in 2016 at Texas A&M University in the group of Prof. Vladislav Yakovlev. My research at Texas A&M spanned a wide range of topics ranging from advanced coherent light generation techniques to developing cutting edge methods in Brillouin microscopy. This includes development and demonstration of coherence brightened oxygen lasing for atmospheric remote sensing, generation of coherent light at the intensity-induced sidebands of a two-level system via strong non-resonant pumping which could be used for XUV generation, and enhanced anti-Stokes Raman generation via mid-infrared two-photon pumping. At the heart of all these techniques is the use of an intense electric field to induce a coherence throughout the medium such that the emitters act collectively. I joined Prof. Maiken Mikkelsen’s group in the spring of 2016. I am interested in utilizing plasmonic nanostructures and metamaterials to develop advanced techniques for coherence-driven and nonlinear light generation as well as creating new approaches to control and manipulate optical fields.

2015:

Gleb Akselrod: I completed my PhD in 2013 at MIT, where I studied the transport and coherence of excitons in organic and nanostructured materials in the group of Prof. Vladimir Bulovic. In the Fall of 2013, I joined the groups of Prof. Maiken Mikkelsen and Prof. David Smith at Duke where I am working on plasmonic nanocavities, antennas, and metamaterials. My research is focused on a versatile antenna geometry known as a patch antenna. Originally developed in the microwave spectral region, we have developed a unique colloidal fabrication process that allows us to make these structures in the visible and IR spectral regions. At the heart of these antennas is a nanoscale gap between a colloidal metal nanoparticle and a metal film. In this this precisely controlledgap, optical fields are strongly enhanced which results in an incredible boosting of a wide range of optical processes, including absorption, spontaneous emission, Raman scattering, and nonlinear generation. Using this plasmonic nanocavity, I have demonstrated the largest ever enhancements in the rate of spontaneous emission rate (1000-times), an effect that can used for ultrafast LEDs and single photon sources. I am also using random arrays of these cavities to create large-area plasmonic metasurfaces that act as perfect light absorbers. Fellow's faculty member: Maiken Mikkelsen

François Amet: I joined Prof. Gleb Finkelstein’s group in the Fall of 2014 after graduating from Stanford, where I worked in David Goldhaber-Gordon’s group. My research explores the low-temperature electronic properties of two-dimensional materials such as graphene, a one-atom thick carbon crystal with a honeycomb lattice. We currently develop heterostructures where superconductivity is induced in a pristine graphene layer in close proximity to superconducting electrodes. Graphene then provides a ballistic channel to investigate the interplay of superconductivity and Dirac fermion physics, while limiting the influence of disorder. In these devices, we study the impact of quantum confinement on superconductivity by flowing a supercurrent through a gate-defined nanoconstriction in bilayer graphene, a regime that yields quantized conductance in the normal state but remains unexplored in the case of supercurrents. Our second project is to determine signatures of specular Andreev reflections at the boundary between monolayer graphene and a superconductor, a peculiar process where incident Dirac electrons are reflected as holes, while a Cooper pair is transmitted on the superconducting side. Fellow's faculty member: Gleb Finkelstein

Jonathan Bares: My current research projects concern the physics of granular materials. Those materials are surprising because on a large scale they can behave like a solid (walking on wet sand on a beach), a liquid (flowing sand between fingers), or a gas (sandstorm in a desert). Hence, open questions are how transitions occur between these states, how collective behaviors may arise and what forms they take, what are the relevant properties of the grains (shape, friction, stiffness), etc. My work focus on the fundamental behavior of near-jamming granular systems, with a particular interest on the effect of shear and friction. To tackle those problems, I use both a 2D and 3D experimental approach. The first, which consists in a 2D Couette-like experiment permits to apply shear strain on photo-elastic grains without inducing shear bands. This allows me to determine the dynamic properties (positions and force chains) for sheared systems of grains below the isotropic jamming. The second is a 3D laser scan which tracks the grain positions and force chains when applying any load on a granular system. This allows me to determine the dynamic of shearing for each 3D shear mode. Fellow's faculty member: Robert P. Behringer