Euler buckling instability and enhanced current blockade in suspended single-electron transistors

TL;DR

This paper theoretically explores how approaching Euler buckling instability in suspended single-electron transistors significantly enhances the low-bias current blockade caused by electromechanical coupling, potentially making it experimentally observable.

Contribution

It reveals that near Euler buckling instability, the current blockade in suspended single-electron transistors is greatly amplified, providing new insights into electromechanical effects in nanoscale devices.

Findings

Current blockade is strongly enhanced near Euler buckling instability.

Bias voltage for transport blockade increases by orders of magnitude.

Mechanism could enable experimental observation of classical current blockade.

Abstract

Single-electron transistors embedded in a suspended nanobeam or carbon nanotube may exhibit effects originating from the coupling of the electronic degrees of freedom to the mechanical oscillations of the suspended structure. Here, we investigate theoretically the consequences of a capacitive electromechanical interaction when the supporting beam is brought close to the Euler buckling instability by a lateral compressive strain. Our central result is that the low-bias current blockade, originating from the electromechanical coupling for the classical resonator, is strongly enhanced near the Euler instability. We predict that the bias voltage below which transport is blocked increases by orders of magnitude for typical parameters. This mechanism may make the otherwise elusive classical current blockade experimentally observable.