Resonantly enhanced nonlinear conductance in long quantum point contacts near pinch-off.
We report on a remarkable resonance in the differential conductance of long quantum point contacts (QPCs) that is observed as a precursor to regular quantized transport. This effect is increasingly pronounced in longer QPCs, in which the differential conductance may resonantly exceed 2e2/h. From a study of the experimental characteristics of this feature, we suggest that it may be associated with the formation of a well-resolved energy gap that opens dynamically as a result of enhanced many-body interactions in long QPCs.
Morimoto
T
T
Graduate School of Science and Technology, Chiba University, Inage-ku, Chiba 263-8522, Japan.
Henmi
M
M
Naito
R
R
Tsubaki
K
K
Aoki
N
N
Bird
J P
JP
Ochiai
Y
Y