Gate-tunable high mobility remote-doped InSb/In_{1-x}Al_{x}Sb quantum well heterostructures

TL;DR

This paper reports on gate-tunable InSb/In_{1-x}Al_{x}Sb quantum wells with high mobility exceeding 200,000 cm^{2}/Vs, demonstrating complete depletion, quantum Hall effects, and low-resistance contacts at cryogenic temperatures.

Contribution

It introduces a novel heterostructure with high mobility, effective gate control, and low contact resistance, advancing quantum well device performance.

Findings

Achieved 2DEG mobility over 200,000 cm^{2}/Vs at 1.8K.

Demonstrated complete 2DEG depletion with minimal hysteresis.

Observed integer quantum Hall effect down to Landau level 1.

Abstract

Gate-tunable high-mobility InSb/In_{1-x}Al_{x}Sb quantum wells (QWs) grown on GaAs substrates are reported. The QW two-dimensional electron gas (2DEG) channel mobility in excess of 200,000 cm^{2}/Vs is measured at T=1.8K. In asymmetrically remote-doped samples with an HfO_{2} gate dielectric formed by atomic layer deposition, parallel conduction is eliminated and complete 2DEG channel depletion is reached with minimal hysteresis in gate bias response of the 2DEG electron density. The integer quantum Hall effect with Landau level filling factor down to 1 is observed. A high-transparency non-alloyed Ohmic contact to the 2DEG with contact resistance below 1{\Omega} \cdot mm is achieved at 1.8K.