Effect of carrier heating on photovoltage in FET

TL;DR

This paper investigates how carrier heating influences photovoltage in FETs, revealing that nonuniform electron heating significantly enhances current generation beyond traditional models.

Contribution

It introduces a detailed theoretical analysis of carrier heating effects on photovoltage in FETs using the Boltzmann equation framework.

Findings

Carrier heating can dominate the photovoltage in FETs.

The electron heating effect is linked to the wave's extinction coefficient.

Heating effects can greatly exceed predictions ignoring heating.

Abstract

We have calculated, within the framework of the Boltzmann equation, a dc electric current and emf in a two-dimensional system induced by the high-frequency field of an electromagnetic wave or the electric field of a plasmon wave. It is established that the generated current consists of two contributions, one of which is proportional to the real part of the wave vector projection of the exciting wave onto the interface plane and represents the electron drag effect, and the other contribution is proportional to the extinction coefficient of the wave in the interface plane. It is shown that the main cause of the second contribution is a nonuniform electron heating created by the wave and controlled by the energy relaxation time of the electron gas. In FET the heating mechanism of the electric-current formation can remarkably exceed the current calculated neglecting the heating.