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A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
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Quantum electrodynamics of photonic time crystals
Junhyeon Bae1, Kyungmin Lee2, Bumki Min3
1Department of Physics, Chung-Ang University, Seoul, Republic of Korea.
Nature Communications
|December 19, 2025
Summary
Quantum models of photonic time crystals reveal that classical momentum gaps stem from quantum phase transitions. This leads to irreversible decay in atomic Rabi oscillations, opening new avenues in quantum photonics.
Area of Science:
- Quantum optics
- Condensed matter physics
- Non-equilibrium physics
Background:
- Photonic time crystals exhibit phenomena like wave amplification due to time-periodic modulation.
- The quantum behavior of photonic time crystals coupled to atomic dipoles is not well understood.
- Classical descriptions of photonic time crystals do not fully capture their quantum manifestations.
Purpose of the Study:
- To develop a quantum electrodynamical model for photonic time crystals.
- To explore the quantum manifestation of classical phenomena like the momentum gap.
- To investigate the interaction of two-level atoms with photonic time crystals.
Main Methods:
- Developed a quantum electrodynamical model for photonic time crystals.
- Utilized an effective Hamiltonian perspective to analyze the system.
- Investigated the quantum phase transition and its effect on atomic behavior.
Main Results:
- The classical momentum gap arises from a quantum localization-delocalization phase transition.
- Classical exponential field growth corresponds to wave-packet acceleration in synthetic space.
- Embedded atoms exhibit irreversible decay in Rabi oscillations due to photonic delocalization.
Conclusions:
- Photonic time crystals provide a platform for studying non-equilibrium quantum photonics.
- Time domain engineering can control light-matter interactions.
- A novel quantum phenomenon of irreversible decay to a mixed state was observed.
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