Superradiant Decay of Cyclotron Resonance of Two-Dimensional Electron Gases

Qi Zhang, Rice University
Takashi Arikawa, Rice University
Eiji Kato, Advantest America Inc.
John L. Reno, Sandia National Laboratory
Wei Pan, Sandia National Laboratory
John D. Watson, Purdue University, Birck Nanotechnology Center
Michael J. Manfra, Purdue University, Birck Nanotechnology Center
Michael A. Zudov, University of Minnesota
Mikhail Tokman, Russian Academy of Sciences
Maria Erukhimova, Russian Academy of Sciences
Alexey Belyanin, Texas A & M University - College Station
Junichiro Kono, Rice University

Date of this Version



This is the publisher PDF of Zhang, Q; Arikawa, T; Kato, E; Reno, JL; Pan, W; Watson, JD; Manfra, MJ; Zudov, MA; Tokman, M; Erukhimova, M; Belyanin, A; Kono, J. "Superradiant Decay of Cyclotron Resonance of Two-Dimensional Electron Gases." Physical Review Letters, 113:4. 047601. 2014. Copyright APS, available at


We report on the observation of collective radiative decay, or superradiance, of cyclotron resonance (CR) in high-mobility two-dimensional electron gases in GaAs quantum wells using time-domain terahertz magnetospectroscopy. The decay rate of coherent CR oscillations increases linearly with the electron density in a wide range, which is a hallmark of superradiant damping. Our fully quantum mechanical theory provides a universal formula for the decay rate, which reproduces our experimental data without any adjustable parameter. These results firmly establish the many-body nature of CR decoherence in this system, despite the fact that the CR frequency is immune to electron-electron interactions due to Kohn's theorem.


Nanoscience and Nanotechnology