Unusually strong near-infrared photoluminescence of highly transparent bulk InSe flakes

Published

September 23, 2024

Author(s)

Jamie Geng, Dehui Zhang, Inha Kim, Hyong Min Kim, Naoiki Higashitarumizu, I K M Reaz Rahman, Lam Lam, Joel W. Ager III, Albert Davydov, Sergiy Krylyuk, Ali Javey

Abstract

Bulk γ-InSe has a direct bandgap of 1.24 eV, which corresponds to near infrared wavelengths (λ = 1.0 µm) useful in optoelectronic applications from biometric detectors to silicon photonics. However, its potential for optoelectronic applications is largely untapped due in part to the lack of quantitative studies of its optical properties. Here, the unusually low absorptance and high photoluminescence quantum efficiency of single-crystalline InSe flakes with thickness in the hundreds of nanometers are studied. InSe emits brightly at room temperature from its direct bandgap with a peak photoluminescence quantum yield (PLQY) of 20%, despite displaying indirect bandgap like low absorption coefficient due to the symmetry of its crystal structure. By performing pump-dependent PLQY measurements, the radiative and nonradiative recombination coefficients are extracted, including the Shockley-Read-Hall and Auger coefficients. Finally, a proof-of-concept alternating current electroluminescent device at low temperature is demonstrated to show the promise of InSe in optoelectronic technology such as highly transparent, bright NIR light sources.

Citation

Advanced Functional Materials

Volume

35

Pub Type

Journals

Download Paper

https://doi.org/10.1002/adfm.202413672

Local Download

Keywords

Indium Selenide, Photoluminescence Quantum Yield, Absorption

Citation

Geng, J. , Zhang, D. , Kim, I. , Kim, H. , Higashitarumizu, N. , Rahman, I. , Lam, L. , Ager III, J. , Davydov, A. , Krylyuk, S. and Javey, A. (2024), Unusually strong near-infrared photoluminescence of highly transparent bulk InSe flakes, Advanced Functional Materials, [online], https://doi.org/10.1002/adfm.202413672, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=958102 (Accessed February 15, 2025)