Presentation Details
| Exceptionally Bright Near-Band-Edge Emission in an Earth-Abundant, Defect-Tolerant Semiconductor (yes) Smitakshi Goswami1, Zhenkun Yuan1, Genevieve Amobi2, Sita Dugu3, Gideon Kassa1, Kirill Kovnir2, Geoffroy Hautier1, 4, Sage Bauers3, Jifeng Liu1. 1Dartmouth College, Hanover, NH, USA.2Iowa State University, Ames, IA, USA.3National Lab of the Rockies, Golden, CO, USA.4Rice University, Houston, TX, USA |
Abstract
Abstract— The scalable deployment of photovoltaic technologies requires defect-tolerant, earth-abundant semiconductors that combine optimal bandgaps with strong intrinsic optoelectronic quality. Here, we identify a stable, earth-abundant semiconductor with an optical bandgap of ~1.47 eV, near the single-junction photovoltaic optimum, and present the first systematic experimental optical investigation of this material across powder, crystal, and thin-film forms. Room-temperature photoluminescence measurements reveal dominant near-band-edge emission with no observable sub-bandgap defect-related luminescence, indicating suppressed non-radiative recombination. Remarkably, crystalline samples exhibit exceptionally bright emission exceeding that of reference GaAs under identical excitation conditions, highlighting unusually high intrinsic radiative efficiency. Temperature-dependent photoluminescence reveals sharp excitonic features at cryogenic temperatures in powders and crystals, while thin films show broadened emission consistent with microstructural disorder or strain. The experimentally extracted bandgaps are in close agreement with hybrid-functional (HSE06) first-principles calculations, establishing this material as a promising, defect-tolerant, and scalable photovoltaic absorber.
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No part of this publication may be reproduced, distributed, or transmitted in any form or by any means, including photocopying, recording, or other electronic or mechanical methods, without the prior written permission of the author.