Room-temperature polariton condensate in a two-dimensional hybrid perovskite

TL;DR

This paper reports the first observation of room-temperature polariton condensation in 2D halide perovskites, demonstrating potential for new polariton lasers and optoelectronic devices based on these materials.

Contribution

It demonstrates room-temperature cavity exciton-polariton condensation in 2D perovskite crystals, a significant step forward in polaritonics at ambient conditions.

Findings

Polariton condensation threshold of 6.76 fJ per pulse

Observation of spatial coherence with g(1)≈0.6

Strong nonlinear optical response detected

Abstract

Layered 2D halide perovskites are chemically synthesized realizations of quantum well stacks with giant exciton oscillator strengths, tunable emission spectra and very large exciton binding energies. While these features render 2D halide perovskites a promising platform for room-temperature polaritonics, bosonic condensation and polariton lasing in 2D perovskites have so far remained elusive at ambient conditions. Here, we demonstrate room-temperature cavity exciton-polariton condensation in mechanically exfoliated crystals of the 2D Ruddlesden-Popper iodide perovskite $(BA)_{2}(MA)_{2}Pb_{3}I_{10}$ in an open optical microcavity. We observe a polariton condensation threshold of $P_{th}=6.76 fJ$ per pulse and detect a strong non-linear response. Interferometric measurements confirm the spontaneous emergence of spatial coherence across the condensate with an associated first-order autocorrelation reaching $g^{(1)}\approx 0.6$. Our results lay the foundation for a new class of room-temperature polariton lasers based on 2D halide perovskites with great potential for hetero-integration with other van-der-Waals materials and combination with photonic crystals or waveguides.