In situ tuning of dynamical Coulomb blockade on Andreev bound states in hybrid nanowire devices

TL;DR

This paper presents an on-chip circuit that allows in situ gate tuning of dynamical Coulomb blockade in hybrid nanowire devices, enabling real-time control and study of zero-energy states like Andreev states.

Contribution

It introduces a novel gate-tunable circuit for dynamical Coulomb blockade in InAs-Al nanowires, allowing in situ adjustment of interaction strength.

Findings

Observed transition from zero-bias peak to split peaks in conductance.

Demonstrated in situ tuning of interaction strength.

Enabled tracking of state evolution during tuning.

Abstract

Electron interactions in quantum devices can exhibit intriguing phenomena. One example is assembling an electronic device in series with an on-chip resistor. The quantum laws of electricity of the device is modified at low energies and temperatures by dissipative interactions induced by the resistor, a phenomenon known as dynamical Coulomb blockade (DCB). The DCB strength is usually non-adjustable in a fixed environment defined by the resistor. Here, we design an on-chip circuit for InAs-Al hybrid nanowires where the DCB strength can be gate-tuned in situ. InAs-Al nanowires could host Andreev or Majorana zero-energy states. This technique enables tracking the evolution of the same state while tuning the DCB strength from weak to strong. We observe the transition from a zero-bias conductance peak to split peaks for Andreev zero-energy states. Our technique opens the door to in situ tuning interaction strength on zero-energy states.