TY - JOUR

T1 - Scanning of Electronic States in a Quantum Point Contact Using Asymmetrically Biased Side Gates

AU - Pokhabov, D. A.

AU - Pogosov, A. G.

AU - Zhdanov, E. Yu

AU - Bakarov, A. K.

N1 - This work was supported by the Russian Science Foundation (project no. 22-12-00343, measurements) and by the Ministry of Science and Higher Education of the Russian Federation (project no. FWGW-2022-0011, fabrication and characterization of the samples).

PY - 2023/2

Y1 - 2023/2

N2 - The conductance of a trench-type quantum point contact (QPC) with side gates has been experimentally investigated over a wide range of gate voltages. The performed measurements, in which the asymmetric gate bias modifies the confinement potential while the sum of the gate voltages populates it with electrons, made it possible to scan the electron states in the QPC. Analysis of the experimental data revealed an unusual four-well shape of the confining potential in a single QPC. The rather complicated transconductance plot measured can be divided into its component parts—the contributions of the four separate conducting channels. Different electron states observed in the experiment have been associated with a certain number of filled one-dimensional (1D) subbands belonging to different channels. A whole network of degeneration events of 1D subbands in parallel channels has been found. Almost every such event was experimentally manifested by anticrossings observed both for small and large numbers of filled 1D subbands.

AB - The conductance of a trench-type quantum point contact (QPC) with side gates has been experimentally investigated over a wide range of gate voltages. The performed measurements, in which the asymmetric gate bias modifies the confinement potential while the sum of the gate voltages populates it with electrons, made it possible to scan the electron states in the QPC. Analysis of the experimental data revealed an unusual four-well shape of the confining potential in a single QPC. The rather complicated transconductance plot measured can be divided into its component parts—the contributions of the four separate conducting channels. Different electron states observed in the experiment have been associated with a certain number of filled one-dimensional (1D) subbands belonging to different channels. A whole network of degeneration events of 1D subbands in parallel channels has been found. Almost every such event was experimentally manifested by anticrossings observed both for small and large numbers of filled 1D subbands.

UR - https://www.scopus.com/record/display.uri?eid=2-s2.0-85153106933&origin=inward&txGid=39cdde450fbaf3e24b4d006e4d7f9d50

UR - https://www.mendeley.com/catalogue/5cc8e485-7464-3397-927c-f9d3cbf92031/

U2 - 10.1134/S0021364022603049

DO - 10.1134/S0021364022603049

M3 - Article

VL - 117

SP - 299

EP - 305

JO - JETP Letters

JF - JETP Letters

SN - 0021-3640

IS - 4

ER -