High Photovoltaic Quantum Efficiency in Ultrathin van der Waals Heterostructures

TL;DR

This paper demonstrates ultrathin van der Waals heterostructures with high external quantum efficiencies over 50% and internal collection efficiencies above 70%, achieved through experimental and simulation methods.

Contribution

It presents the first experimental demonstration of ultrathin heterostructures with over 50% external quantum efficiency and high internal collection efficiency.

Findings

External quantum efficiency exceeds 50%.

Absorbance surpasses 90%.

Internal collection efficiency exceeds 70%.

Abstract

We report experimental measurements for ultrathin (< 15 nm) van der Waals heterostructures exhibiting external quantum efficiencies exceeding 50%, and show that these structures can achieve experimental absorbance > 90%. By coupling electromagnetic simulations and experimental measurements, we show that pn WSe2/MoS2 heterojunctions with vertical carrier collection can have internal photocarrier collection efficiencies exceeding 70%.