# Microscopic origin of the bolometric effect in graphene

## TL;DR

This paper provides a detailed microscopic analysis of the bolometric effect in graphene, showing how doping influences its contribution to photoresponse through temperature and conductivity changes.

## Contribution

It introduces a microscopic model based on semiconductor Bloch equations to analyze the bolometric effect in graphene under optical excitation and electric bias.

## Key findings

- Bolometric effect magnitude depends on optically induced temperature increase and conductivity change.
- The importance of the bolometric effect increases with doping, showing a parabolic dependence.
- The model reveals the microscopic carrier dynamics responsible for the bolometric response.

## Abstract

While the thermoelectric and photoconduction effects are crucial in pristine and low-doped graphene, the bolometric effect is known to dominate the photoresponse in biased graphene. Here, we present a detailed microscopic investigation of the photoresponse due to the bolometric effect in graphene. Based on the semiconductor Bloch equations, we investigate the time- and momentumresolved carrier dynamics in graphene in the presence of a constant electric field under optical excitation. The magnitude of the bolometric effect is determined by the optically induced increase of temperature times the conductivity change. Investigating both factors independently, we reveal that the importance of the bolometric effect in the high-doping regime can be mostly ascribed to the latter showing a parabolic dependence on the doping.