Tag: Physical Review Letters
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Cracking the Code of Chaos with Time-Delay Invariants
Revealing the Hidden Order in Chaos From the weather’s swirling patterns to the orbits of distant planets, many of the world’s most important systems behave chaotically. Their paths seem random, but scientists know there is an underlying structure. Traditionally, researchers study these systems through invariant measures—long-term statistical descriptions that capture the overall behavior of a…
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Twice Around To Return Home: A Hidden Reset Button for Spins and Qubits
Introduction: A surprising reset in the world of rotations Rotations lie at the heart of much of modern science and technology. From the precession of nuclear spins in NMR machines to the precise control of qubits in quantum computers, many physical systems evolve through a series of rotations. These sequences can be imagined as walks…
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Spontaneous Emission in Photonic Time Crystals: New Decay
Breakthrough: Spontaneous Emission Reimagined in Time-Varying Media A KAIST-led international collaboration has achieved a landmark result in quantum optics by demonstrating that spontaneous emission behaves in a fundamentally new way inside Photonic Time Crystals (PTCs). Challenging prior predictions, the team shows that the spontaneous emission decay rate is enhanced—not extinguished—by rapid, periodic changes of a…
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First Elucidation Of Spontaneous Emission And Excitation In Photonic Time Crystals
Breakthrough: Spontaneous Emission Gets a Time-Tuned Twist A KAIST-led collaboration has unveiled a surprising twist in how light interacts with matter when the environment itself changes in time. In a study published online in Physical Review Letters on September 23, 2025, researchers from KAIST’s Department of Physics—led by Professor Bumki Min—and partners from the Department…