Room Temperature Continuous-wave Excited Biexciton Emission in CsPbBr3 Nanocrystals

TL;DR

This paper demonstrates room temperature, continuous-wave driven biexciton emission in CsPbBr3 nanocrystals via plasmonic coupling, significantly reducing excitation fluence and enabling advanced quantum light sources.

Contribution

It introduces a novel method to achieve room temperature biexciton emission using plasmonic nanogaps, surpassing previous cryogenic requirements.

Findings

Room temperature biexciton emission achieved in CsPbBr3 nanocrystals.

Giant enhancement of biexciton emission via plasmonic Fano interference.

Excitation fluence reduced by ~10^13 times using Ag nanowire-film nanogaps.

Abstract

Biexcitons are a manifestation of many-body excitonic interactions crucial for quantum information and quantum computation in the construction of coherent combinations of quantum states. However, due to their small binding energy and low transition efficiency, most biexcitons in conventional semiconductors exist either at cryogenic temperature or under femtosecond pulse laser excitation. Here we demonstrate room temperature, continuous wave driven biexciton states in CsPbBr3 perovskite nanocrystals through coupling with a plasmonic nanogap. The room temperature CsPbBr3 biexciton excitation fluence (~100 mW/cm2) is reduced by ~10^13 times in the Ag nanowire-film nanogaps. The giant enhancement of biexciton emission is driven by coherent biexciton-plasmon Fano interference. These results provide new pathways to develop high efficiency non-blinking single photon sources, entangled light sources and lasers based on biexciton states.