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Comprehensive Characterization of Extended Defects in Semiconductor Materials by a Scanning Electron Microscope
Published on: May 28, 2016
Radiative Electronic Bound States in the Continuum from Defects in Semiconductors
Seong Yun Hong1, Liang Z Tan2, Ki Hoon Lee3
1Department of Intelligent Semiconductor Engineering, Incheon National University, Incheon 22012, Republic of Korea.
Nano Letters
|May 25, 2026
Summary
Defect states in semiconductors can be optically active, hosting radiative electronic bound states in the continuum (BICs). This finding enables new defect-based optical systems, including quantum emitters and qubits.
Area of Science:
- Solid-state physics
- Quantum optics
- Materials science
Background:
- Continuum-buried defect states in semiconductors are typically optically inactive due to strong coupling to continuum bands.
- Understanding defect states is crucial for developing advanced semiconductor devices.
Purpose of the Study:
- To demonstrate that continuum-buried defect states can host radiative electronic bound states in the continuum (BICs).
- To investigate the silicon G center as a model system for this phenomenon.
- To establish BICs as a paradigm for defect-based optical systems.
Main Methods:
- Hybrid functional first-principles calculations with Hubbard U correction.
- Analysis of defect state energy-level reordering under optical excitation.
- Computation of temperature-dependent nonradiative lifetimes and comparison with experimental photoluminescence (PL) lifetimes.
Main Results:
- A localized defect state, initially below the valence band maximum (VBM), shifts above VBM upon optical excitation due to exchange-driven energy-level reordering.
- This transition suppresses nonradiative decay, enabling robust radiative emission.
- Calculated nonradiative lifetimes quantitatively reproduce experimental PL lifetimes across temperatures.
Conclusions:
- Continuum-embedded defect states can be stabilized and become optically active.
- Electronic BICs offer a general mechanism for designing efficient defect-based optical systems.
- This research opens avenues for novel quantum emitters and qubits.
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