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Many-body spin related phenomena in ultra-low-disorder quantum wires

D. J. Reilly·G. R. Facer·A. S. Dzurak·B. E. Kane·R. G. Clark·P. J. Stiles·J. L. O'Brien·N. E. Lumpkin·L. N. Pfeiffer·K. W. West
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Abstract

Zero length quantum wires (or point contacts) exhibit unexplained conductance structure close to 0.7 X 2e^2/h in the absence of an applied magnetic field. We have studied the density- and temperature-dependent conductance of ultra-low-disorder GaAs/AlGaAs quantum wires with nominal lengths l=0 and 2 mu m, fabricated from structures free of the disorder associated with modulation doping. In a direct comparison we observe structure near 0.7 X 2e^2/h for l=0 whereas the l=2 mu m wires show structure evolving with increasing electron density to 0.5 X 2e^2/h in zero magnetic field, the value expected for an ideal spin-split sub-band. Our results suggest the dominant mechanism through which electrons interact can be strongly affected by the length of the 1D region.

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D. J. Reilly, G. R. Facer, A. S. Dzurak, B. E. Kane, R. G. Clark, P. J. Stiles, J. L. O'Brien, N. E. Lumpkin, L. N. Pfeiffer, K. W. West. 2000-01-13. Many-body spin related phenomena in ultra-low-disorder quantum wires. https://doi.org/10.1103/physrevb.63.121311

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