LETTER TO THE EDITOR: On the acoustoelectric current in a one-dimensional channel

We report the first observation of the direct current induced by a surface acoustic wave through a quantum point contact defined in a GaAs - AlGaAs two-dimensional electron gas by means of a split gate. We have observed giant oscillations in the acoustoelectric current as a function of gate voltage, with minima corresponding to the plateaux in quantum point contact conductivity. A theoretical consideration is presented which explains the observed peaks in terms of the matching of sound velocity with electron velocity in the upper one-dimensional subband of the quantum point contact.

[1]  A. Wixforth,et al.  Acoustoelectric study of localized states in the quantized Hall effect , 1992 .

[2]  A. C. Churchill,et al.  Experimental study of the acoustoelectric effects in GaAs-AlGaAs heterostructures , 1995 .

[3]  West,et al.  Experimental demonstration of a Fermi surface at one-half filling of the lowest Landau level. , 1993, Physical review letters.

[4]  D. Ritchie,et al.  EFFECT OF TERAHERTZ IRRADIATION ON BALLISTIC TRANSPORT THROUGH ONE-DIMENSIONAL QUANTUM POINT CONTACTS , 1995 .

[5]  Niu,et al.  Towards a quantum pump of electric charges. , 1990, Physical review letters.

[6]  West,et al.  Anomalous sound propagation at nu =1/2 in a 2D electron gas: Observation of a spontaneously broken translational symmetry? , 1990, Physical review letters.

[7]  K. Yamanouchi,et al.  Nanometer Electrode Fabrication Technology Using Anodic Oxidation Resist and Application to Unidirectional Surface Acoustic Wave Transducers , 1994 .

[8]  Ritchie,et al.  Charging effects and the excitation spectrum of a quantum dot formed by an impurity potential. , 1993, Physical review. B, Condensed matter.

[9]  Weimann,et al.  Surface acoustic waves on GaAs/AlxGa1-xAs heterostructures. , 1989, Physical review. B, Condensed matter.

[10]  John H. Davies,et al.  The Smallest Electronic Device: An Electron Waveguide , 1994 .

[11]  David A. Ritchie,et al.  A new mechanism for high-frequency rectification in a ballistic quantum point contact , 1994 .

[12]  Weimann,et al.  Quantum oscillations in the surface-acoustic-wave attenuation caused by a two-dimensional electron system. , 1986, Physical review letters.

[13]  A. Wixforth,et al.  Ultrasonic approach to the integer and fractional quantum Hall effect , 1994 .

[14]  Simmons,et al.  Effect of spatial dispersion on acoustoelectric current in a high-mobility two-dimensional electron gas. , 1995, Physical review. B, Condensed matter.