Experimental investigation of the ratchet effect in a two-dimensional electron system with broken spatial inversion symmetry

TL;DR

This paper presents experimental evidence of directed electron transport in a two-dimensional asymmetric system induced by microwave irradiation, demonstrating controllable current direction and potential applications in microwave detection.

Contribution

It experimentally demonstrates the ratchet effect in a 2D electron system with broken symmetry, showing control of electron flow via microwave polarization.

Findings

Electron transport direction is controllable by microwave polarization.

The ratchet effect depends on magnetic field and temperature.

Potential for new microwave detectors and current generators.

Abstract

We report on experimental evidence of directed electron transport, induced by external linear-polarized microwave irradiation, in a two-dimensional spatially-periodic asymmetrical system called ratchet. The broken spatial symmetry was introduced in a high mobility two-dimensional electron gas based on AlGaAs/GaAs heterojunction, by patterning an array of artificial semi-discs-shaped antidots. We show that the direction of the transport is efficiently changed by microwave polarization. The dependence of the effect on magnetic field and temperature is investigated. This represents a significant step towards the realization of new microwave detectors and current generators.