High-temperature superfluorescence in methyl ammonium lead iodide

Abstract

Light-matter interactions can create and manipulate collective many-body phases in solids 1-3 , which are promising for the realization of emerging quantum applications. However, in most cases these collective quantum states are fragile, with a short decoherence and dephasing time, limiting their existence to precision tailored structures under delicate conditions such as cryogenic temperatures and/or high magnetic fields. In this work, we discovered that the archetypal hybrid perovskite, MAPbI3 thin films, exhibit such a collective coherent quantum many-body phase, namely superfluorescence, at 78 K and above. Pulsed laser excitation first creates a population of high energy electron-hole pairs, which quickly

Terahertz Nanoimaging of Perovskite Solar Cell Materials

“…The extraordinary device performance based on hybrid metal halide (HMH) perovskites has motivated the intense study of their fundamental optoelectronic properties and exotic collective excitations, such as Rydberg excitons, Rashba, polaronic effects, − and superfluorescence . The highly intertwined properties responsible for optimizing photoenergy conversion efficiency and stability include grain boundary (GB) defects, charge filling of defect traps, and material degradation.…”

Transient Lasing Behaviors in MAPbBr3 Perovskite Microcavities

“…EPs exist in a strong exciton−photon coupling regime with characteristic anticrossing dispersion curves, 12 while SF requires complex structures and harsh conditions to form macrocoherence among excited carriers. 13,16 The EHP is induced at a high carrier density over the Mott transition. The thresholds of stimulated emission under an intense femtosecond laser excitation range from several to several tens of μJ/ cm 2 in perovskite materials.…”

“…Although many efforts have been made to optimize the lasing performance of perovskite-based devices, a consensus on its physical origins has not been fully understood yet. − Exciton polaritons (EPs), superfluorescence (SF), and electron–hole plasma (EHP) are the most discussed mechanisms with distinctive spectroscopic performance. EPs exist in a strong exciton–photon coupling regime with characteristic anticrossing dispersion curves, while SF requires complex structures and harsh conditions to form macrocoherence among excited carriers. , The EHP is induced at a high carrier density over the Mott transition. The thresholds of stimulated emission under an intense femtosecond laser excitation range from several to several tens of μJ/cm 2 in perovskite materials .…”

Magnetically Tunable Spontaneous Superradiance from Mesoscopic Perovskite Emitter Clusters

“…This phenomenon, first predicted by Dicke, is called superradiance, which is one form of collective emission . Since its first experimental demonstration in molecular gas, superradiance has been observed in many other physical systems such as atomic gases, , atomic ensembles, − and solid-state systems, including point defects, , quantum dot (nanocrystal) ensembles, − quantum wells, , and thin films . Superradiance has been utilized to create a laser with ultranarrow line width. , Moreover, there is a close relationship between superradiance and entanglement .…”