Pumping properties of the hybrid single-electron transistor in dissipative environment

TL;DR

This study investigates the pumping behavior of a hybrid normal-metal/superconductor single-electron transistor in a high-resistance environment, showing improved performance at low frequencies but reduced efficiency at higher frequencies due to damping and heating effects.

Contribution

It demonstrates how embedding the device in a high-ohmic environment enhances low-frequency pumping and reduces leakage, providing insights into environmental effects on single-electron transistors.

Findings

Improved pumping and reduced leakage at low frequencies.

Damping and electron heating impair performance at high frequencies.

High-ohmic environment benefits are frequency-dependent.

Abstract

Pumping characteristics were studied of the hybrid normal-metal/superconductor single-electron transistor embedded in a high-ohmic environment. Two 3 micrometer-long microstrip resistors of CrOx with a sum resistance R=80kOhm were placed adjacent to this hybrid device. Substantial improvement of pumping and reduction of the subgap leakage were observed in the low-MHz range. At higher frequencies 0.1-1GHz, a slowdown of tunneling due to the enhanced damping and electron heating negatively affected the pumping, as compared to the reference bare devices.