Quantum point contact in a magnetic field: Far-infrared resonant heating observed in photoconductivity

R. J. Heron, University of Wollongong
R. A. Lewis, University of Wollongong
B. E. Kane, University of New South Wales
G. R. Facer, University of New South Wales
R. G. Clark, University of New South Wales
A. S. Dzurak, University of New South Wales
N. E. Lumpkin, University of New South Wales
R. P. Starrett, University of New South Wales
D. G. Rickel, Los Alamos National Laboratory, Los Alamos
L. N. Pfeiffer, Lucent Technologies, New Jersey
K. W. West, Lucent Technologies, New Jersey

Article comments

This article was originally published as Heron, RJ, Lewis, RA, Kane, BE, Facer, GR, Clark, RG, Dzurak, AS, Lumpkin, NE, Starrett, RP, Rickel, DG, Pfeiffer, LN, West, KW, Quantum point contact in a magnetic field: Far-infrared resonant heating observed in photoconductivity, Applied Physics Letters, 75(20), 1999, 3150-3152. Copyright American Institute of Physics 1999. Original journal article available here

Abstract

We report on the far-infrared photoresponse of a quantum point contact device fabricated on a top-gated GaAs/AlGaAs heterostructure. The top-gated architecture avoids the disorder built into conventional modulation-doped structures. We observe a distinctive far-infrared magneto-photoresponse. This depends on the wavelength of the radiation and on the carrier density, which is controlled by the gate voltage. We conclude by comparison with transport data that the oscillations observed in photoconductivity and which are centred around the cyclotron energy arise from the resonant heating of electrons by the far-infrared radiation.