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Updated: Jun 14, 2025
08:04
Excitonic Hamiltonians for Calculating Optical Absorption Spectra and Optoelectronic Properties of Molecular Aggregates and Solids
Published on: May 27, 2020
8.4K
High-Temperature Excitonic Condensation in 2D Lattice.
Yushuo Xu1, Yuanyuan Wang2, Shiqiang Yu1
1School of Physics, State Key Laboratory of Crystal Materials, Shandong University, Jinan, 250100, China.
Advanced Science (Weinheim, Baden-Wurttemberg, Germany)
|September 6, 2024
Summary
High-temperature bosonic condensation is achieved in 2D Bi2S2Te using indirect excitons. This discovery enables potential applications in quantum computing and dissipationless nanodevices.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Mechanics
Background:
- High-temperature bosonic condensation is crucial for fundamental physics and nanodevices.
- Achieving this state remains a significant experimental and theoretical challenge.
Purpose of the Study:
- To explore the possibility of high-temperature excitonic Bose-Einstein condensation (BEC) and superfluidity in two-dimensional (2D) materials.
- To identify a suitable material platform for realizing these phenomena.
Main Methods:
- Utilized many-body perturbation theory combined with first-principles calculations.
- Investigated the optical generation of spatially indirect excitons in 2D Bi2S2Te.
Main Results:
- Spatially indirect excitons in Bi2S2Te monolayer are dipole/parity allowed, with properties suitable for excitonic condensation (small effective mass, dilute limit).
- Theoretically predicted record-high phase transition temperatures for excitonic BEC (289.7 K) and superfluidity (72.4 K) in atomic thin Bi2S2Te.
- Confirmed Bi2S2Te as a 2D platform for high-temperature excitonic condensation due to bound bosonic states.
Conclusions:
- Bi2S2Te facilitates high-temperature excitonic condensation, offering a novel pathway beyond current paradigms.
- This 2D material holds promise for applications in quantum computing and dissipationless nanodevices.
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