Diffusion Thermopower of Quantum Hall States Measured in Corbino Geometry

Abstract

We have measured the diffusion thermopower of a quantum Hall system in a Corbino setup. A concentric electron-temperature gradient is introduced by irradiating microwaves, via a coplanar waveguide, near the outer rim of a circular mesa of a two-dimensional electron gas. The resulting radial thermovoltages exhibit sawtooth-like oscillations with the magnetic field, taking large positive (negative) values just below (above) integer fillings with sign reversal at the center of the quantum Hall plateaus. The behavior is in agreement with a recent theory [Y. Barlas and K. Yang: Phys. Rev. B 85 (2012) 195107], which treats disorder within the self-consistent Born approximation.

4 pages, 4 figures

References in corpus (2)

• Thermopower as a Possible Probe of Non-Abelian Quasiparticle Statistics in Fractional Quantum Hall Liquids
• Thermopower of Quantum Hall States in Corbino Geometry as a Measure of Quasiparticle Entropy

Cited by in corpus (5)

• Magnetocapacitance oscillations and thermoelectric effect in two-dimensional electron gas irradiated by microwaves
• Thermoelectric cooling properties of a quantum Hall Corbino device
• Thermoelectric properties of the Corbino disk in graphene
• Peltier cooling in Corbino-geometry quantum Hall systems
• Controlled generation and detection of a thermal bias in Corbino devices under the quantum Hall regime