2026-03-05 スタンフォード大学
Atomic-resolution image of a PbSnSe thin film transforming between two ordered phases, which changes how light travels through the material. The boundary between the two phases is shown by the dashed line. | Pooja Reddy
＜関連情報＞
- https://news.stanford.edu/stories/2026/03/infrared-leds-sensors-new-technology-research
- https://advanced.onlinelibrary.wiley.com/doi/10.1002/adom.202503448
- https://pubs.acs.org/doi/full/10.1021/acs.nanolett.5c04974
格子不整合ハイブリッドIV-VI/III-Vヘテロ接合に基づく中赤外LED Mid-Infrared LEDs Based on Lattice-Mismatched Hybrid IV–VI/III–V Heterojunctions
Jarod E. Meyer, Biridiana Rodriguez, Leland Nordin, Kunal Mukherjee
Advanced Optical Materials Published: 16 February 2026
DOI:https://doi.org/10.1002/adom.202503448
ABSTRACT
Light-emitting diodes (LEDs) can bridge the gap between narrow linewidth, expensive lasers and broadband, inefficient thermal globars for low-cost chemical sensing in the mid-infrared (mid-IR). However, the efficiency of III–V-based mid-IR LEDs at room temperature is low, primarily limited by strong nonradiative Auger-Meitner recombination that is only partially overcome with complex quantum-engineered active regions. Here, we exploit the intrinsically low Auger-Meitner recombination rates of the IV–VI semiconductors PbSe and PbSnSe, while leveraging the mature III–V platform through the fabrication of hybrid heterojunctions that mediate the ∼8% lattice mismatch to GaAs. Electrically injected n-PbSe/p-GaAs LEDs emit at 3.8 µm with output powers up to 400 µW under pulsed operation and a peak wall plug efficiency of 0.08% at room temperature, approaching the performance of commercial III–V LEDs at similar wavelengths. Incorporating 7% Sn extends the emission to 5 µm in GeSe/PbSnSe/GaAs LEDs with output powers up to 45 µW. Notably, both devices operate despite threading dislocation densities on the order of 109 cm−2, underscoring the potential of hybrid IV–VI/III–V heterojunction architectures. We show that combining the complementary advantages of IV–VI and III–V semiconductors offers a simple and efficient mid-IR optoelectronic platform for a rapidly expanding set of applications.
エピタキシャル制御と複屈折コントラストによるIV-VI族薄膜の可逆的多形スイッチング Reversible Polymorph Switching in IV–VI Thin Films with Epitaxial Control and Birefringence Contrast
Pooja D. Reddy,Virat Tara,Arturas Vailionis,Arka Majumdar,Kunal Mukherjee
Nano Letters Published: December 26, 2025
DOI:https://doi.org/10.1021/acs.nanolett.5c04974
Abstract
Reversible polymorphic transformations provide a powerful route to tune the functionality in semiconductors. We demonstrate a cyclable phase transformation between the rocksalt cubic and layered orthorhombic structures in epitaxial PbSnSe thin films on GaAs(001). This thermally driven transformation occurs between −60 and 150 °C, with the transformation temperature depending on alloy composition. Subtle atomic displacements between polymorphs allow the transformation while retaining epitaxial registry for both states, while the dramatic change in symmetry drives a transition from an optically isotropic to birefringent state, with an index change exceeding Δn = 1. Microstructural analysis reveals a transformation involving low-energy interfaces that coherently accommodates a 3% out-of-plane lattice mismatch. Thermal cycling shows limited endurance at present, tentatively attributed to defect accumulation at phase boundaries, but annealing at increased temperatures indicates that the transformation remains fundamentally reversible. These findings position PbSnSe among a small set of ultratunable semiconductors compatible with epitaxial integration for optoelectronic applications.
