Acoustic charge transport in n-i-n three terminal device

TL;DR

This paper introduces a novel acoustic charge transport device using a n-i-n lateral junction and in-plane gates, enabling flexible signal processing and modulation of acoustoelectric current.

Contribution

It presents an original device architecture replacing standard contacts with a n-i-n junction and in-plane gates, enhancing control and versatility in acoustic charge transport.

Findings

Surface acoustic waves can pick up electrons from the n-i-n junction.

The acoustoelectric current can be modulated by lateral in-plane gates.

The device operates with both voltage and current injection methods.

Abstract

We present an unconventional approach to realize acoustic charge transport devices that takes advantage from an original input region geometry in place of standard Ohmic input contacts. Our scheme is based on a n-i-n lateral junction as electron injector, an etched intrinsic channel, a standard Ohmic output contact and a pair of in-plane gates. We show that surface acoustic waves are able to pick up electrons from a current flowing through the n-i-n junction and steer them toward the output contact. Acoustic charge transport was studied as a function of the injector current and bias, the SAW power and at various temperatures. The possibility to modulate the acoustoelectric current by means of lateral in-plane gates is also discussed. The main advantage of our approach relies on the possibility to drive the n-i-n injector by means of both voltage or current sources, thus allowing to sample and process voltage and current signals as well.