This event has ended. View the official site or create your own event → Check it out
This event has ended. Create your own
View analytic
Friday, August 15 • 08:30 - 10:30
Quantum Hall Effects IV

Sign up or log in to save this to your schedule and see who's attending!

Click here to view Abstracts


Oral: Stephan Baer
Measurements of Quasi-Particle Tunneling in the Second Landau Level
Co-authors: Clemens Rössler, Thomas Ihn, Klaus Ensslin, Christian Reichl, Werner Wegscheider

Oral: Lina Bockhorn
Negative Magnetoresistance Induced by Rare Strong Scatterers
Co-authors: Igor V. Gornyi, Dieter Schuh, Christian Reichl, Werner Wegscheider, Rolf J. Haug

Oral: Milan Orlita
Massless Fermions in 2D & 3D: Infrared Magneto-Spectroscopy Studies
Co-authors: N/A 

Solid-state physics and quantum electrodynamics, with its relativistic (massless) particles, meet in steadily expanding class of materials. Those include, 1D carbon nanotubes, 2D graphene or topological-insulator surfaces, and most recently, the systems with 3D conical dispersion - with Weyl, Dirac or Kane fermions. In this talk, I will review how the linear dispersion impacts the (magneto-) optical properties of these systems.

We focus on two representative materials: a 2D graphene and bulk HgCdTe which displays the 3D conical dispersion when tuned to the point of the semiconductor-to-semimetal transition. We show that it is the number of dimensions, which defines the (joint) density of states, and in consequence, the simple physical quantities such as absorption of light - dispersionless in graphene but displaying a linear-in-photon-energy dependence in HgCdTe. In magnetic field, the optical response is determined by by electronic excitations between discrete or dispersion Landau levels (in 2D or 3D), both, however, with a typical for relativistic particles, square root dependence on the magnetic-field. Further relativistic effects may appear, depending on the strength of spin-orbit coupling. Spin-related effects are rather absent in the optical response of graphene which exhibits a weak spin-orbit coupling. Instead, we observe a pronounced spin splitting of levels in HgCdTe, which follows the square-root-magnetic-field dependence - a well-established signature of relativistic particles.

Oral: Masayuki Hashisaka
Fractional Charge Tunneling through a Local Fractional Quantum Hall Region
Co-authors: Tomoaki Ota, Koji Muraki, Toshimasa Fujisawa

Oral: Ramesh Mani
Size Dependent Giant Magnetoresistance in Millimeter-Sized GaAs/AlGaAs Devices
Co-authors: Annika Kriisa, Werner Wegscheider

Oral: Stephan Smolka
Cavity Quantum Electrodynamics as a Sensitive Probe of Many-Body Physics in Two Dimensional Electron Gases 
Co-authors: Wolf Wüster, Florian Haupt, Stefan Faelt, Werner Wegscheider, Atac Imamoglu 


Session Chairs

Milan Orlita

Laboratoire National des Champs Magnétiques Intenses, CNRS
Dr. Milan Orlita received his B.S. and Ph.D. (2006) from the Charles University in Prague, Czech Republic. Currently, he is a postdoctoral research fellow at Laboratoire National des Champs Magnetiques Intenses, CNRS, Grenoble, France. He is also affiliated with the Academy of Sciences of the Czech Republic. He has published extensively on optical measurements of solid-state systems, especially the graphene layers in recent years.

Friday August 15, 2014 08:30 - 10:30
Room 18AB

Attendees (5)