Resonant Photovoltaic Effect in Surface-State Electrons on Liquid Helium

TL;DR

This paper reports the discovery of an ultra-strong photovoltaic effect in surface-state electrons on liquid helium, caused by resonant microwave absorption leading to significant electron energy gain and a nonequilibrium distribution.

Contribution

It presents the first observation of a resonant photovoltaic effect in a two-dimensional electron system on liquid helium, revealing a new nonequilibrium phenomenon under microwave irradiation.

Findings

Ultra-strong photovoltaic effect observed

Effect linked to resonant intersubband microwave absorption

Electrostatic energy exceeds other relevant energies by orders of magnitude

Abstract

We observed an ultra-strong photovoltaic effect induced by resonant intersubband absorption of microwaves in a two-dimensional electrons system on the surface of liquid helium. The effect emerges in the regime of microwave-induced vanishing of dissipative conductance reported previously [D. Konstantinov and K. Kono: Phys. Rev. Lett. 105 (2010) 226801)] and is characterized by a nonequilibrium spatial distribution of electrons in the confining electrostatic potential. The electrostatic energy acquired by an electron exceeds other relevant energies by several orders of magnitude.