Excitonic gain and laser emission from mixed-cation halide perovskite thin films

Chen, Songtao; Nurmikko, Arto

doi:10.1364/optica.5.001141

Title: Excitonic gain and laser emission from mixed-cation halide perovskite thin films

Journal Article · 20 September 2018 · Optica

DOI: https://doi.org/10.1364/optica.5.001141 · OSTI ID:1471743

^[1]; Nurmikko, Arto ^[2]

Brown Univ., Providence, RI (United States). School of Engineering
Brown Univ., Providence, RI (United States). School of Engineering, and Dept. of Physics

Organic–inorganic halide perovskites have recently developed into a potential semiconductor coherent light emitter candidate beyond their promise in solar cell applications. However, despite the ample demonstrations of perovskite lasers, experimental results on the origin of optical gain in perovskites are still elusive. Here, we analyze the excitonic gain in the green from mixed-cation halide perovskites Cs_0.17[CH(NH₂)₂]_0.83PbBr₃ (Cs_0.17FA_0.83PbBr₃) by both low temperature absorption/emission spectroscopies and ultrafast pump–probe transient absorption experiments. The perovskite thin films show a robust excitonic feature up to room temperature, with estimated exciton binding energy E_b = 43.8 meV, which can be maintained under high electronic excitations that are required for lasers. By using a high-quality (Q = 1350) vertical cavity consisting of sputtered dielectric HfO₂/SiO₂ distributed Bragg reflectors with perovskite optical gain medium embedded inside, we have demonstrated excitonic-gain-enabled optically pumped lasing, with improved threshold of 13.5 ± 1.4 μJ/cm² and device longevity lifetime >35 h (10⁸ laser shots) at ambient environment under sustained pulsed optical excitations (3.493 eV, τ_pulse = 0.34 ns, 1 kHz). Understanding and exploiting excitonic gain from perovskite thin film materials may help to further boost the performance of perovskite-based lasers.

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Research Organization:: Brown Univ., Providence, RI (United States)

Sponsoring Organization:: USDOE

Grant/Contract Number:: FG02-07ER46387

OSTI ID:: 1471743

Alternate ID(s):: OSTI ID: 1502474

Journal Information:: Optica, Vol. 5, Issue 9; ISSN 2334-2536

Publisher:: Optical Society of AmericaCopyright Statement

Country of Publication:: United States

Language:: English

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Cited by: 22 works

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3545458.pdf Chen, Songtao; Nurmikko, Arto https://doi.org/10.6084/m9.figshare.7017164 The current record is supplemented by this text	text	January 2018
3545458.pdf Chen, Songtao; Nurmikko, Arto https://doi.org/10.6084/m9.figshare.7017164.v1 The current record is supplemented by this text	text	January 2018
Excitonic Gain and Laser Emission from Mixed-Cation Halide Perovskite Thin Films Chen, Songtao; Nurmikko, Arto https://doi.org/10.6084/m9.figshare.c.4213100 The current record is supplemented by this collection	collection	January 2018
Excitonic Gain and Laser Emission from Mixed-Cation Halide Perovskite Thin Films Chen, Songtao; Nurmikko, Arto https://doi.org/10.6084/m9.figshare.c.4213100.v1 The current record is supplemented by this collection	collection	January 2018