High Magnetic Field Microwave Conductivity of 2D Electrons in an Array of Antidots

Abstract

We measure the high magnetic field ($B$) microwave conductivity, Re${\sigma }_{xx}$, of a high mobility 2D electron system containing an antidot array. Re${\sigma }_{xx}$ vs frequency ($f$) increases strongly in the regime of the fractional quantum Hall effect series, with Landau filling $1/3<\nu <2/3$. At microwave $f$, Re${\sigma }_{xx}$ vs $B$ exhibits a broad peak centered around $\nu =1/2$. On the peak, the 10 GHz Re${\sigma }_{xx}$ can exceed its dc-limit value by a factor of 5. This enhanced microwave conductivity is unobservable for temperature $T\gtrsim 0.5$ K, and grows more pronounced as $T$ is decreased. The effect may be due to excitations supported by the antidot edges, but different from the well-known edge magnetoplasmons.

4 pages, 3 figures, revtex4

References in corpus (1)

• Reconstruction of Fractional Quantum Hall Edges

Cited by in corpus (5)

• Edge reconstruction in the fractional quantum Hall regime
• Time-resolved impulse response of the magnetoplasmon resonance in a two-dimensional electron gas
• Far-infrared photo-conductivity of electrons in an array of nano-structured antidots
• Collective edge modes in fractional quantum Hall systems
• Instrumentation of a high-sensitivity microwave vector detection system for low-temperature applications