The Berry Phase Rectification Tensor and The Solar Rectification Vector

TL;DR

This paper defines the Berry Phase Rectification Tensor as a material property related to Berry phases, and introduces the Solar Rectification Vector as a measure of photo-current generation under black-body radiation, supported by first-principles calculations.

Contribution

It presents an operational definition of the Berry Phase Rectification Tensor and introduces the Solar Rectification Vector, linking Berry phases to photovoltaic responses.

Findings

Calculated the Berry Phase Rectification Tensor for TaAs and LiAsSe2.

Identified large shift currents near solar radiation peak in LiAsSe2.

Demonstrated the intrinsic nature of the tensor under time-reversal symmetry.

Abstract

We introduce an operational definition of the Berry Phase Rectification Tensor as the second-order change of polarization of a material in response to an ideal short pulse of an electric field. Under time-reversal symmetry this tensor depends exclusively on the Berry phases of the Bloch bands and not their energy dispersions, making it an intrinsic property to each material which contains contributions from both the inter-band shift currents and the intra-band Berry Curvature Dipole. We also introduce the Solar Rectification Vector as a technologically relevant figure of merit for a bulk photo-current generation under ideal black-body radiation in analogy with the classic solar cell model of Shockley and Queisser. We perform first-principles calculations of the Berry Phase Rectification Tensor and the Solar Rectification Vector for the Weyl semimetal TaAs and the insulator LiAsSe2 which features large shift currents close to the peak of solar radiation intensity.