Birth of Light from the Quantum Void ⚡ экспресс
Equilibrium quantum phase transitions radically change the ground state of light-matter systems, but the emerging quantum correlations (squeezing, entanglement) remain experimentally inaccessible because they are associated with virtual excitations of the ground state. We investigate how nonadiabatic modulation of a Hamiltonian parameter can convert these virtual excitations into real photons—giving rise to quantum vacuum radiation. We show that proximity to the critical point strongly enhances the flux of emitted photons and the nonclassical nature of the radiation, even under conditions where thermal fluctuations should dominate. Moreover, multiphoton processes become significant even at small modulation amplitudes; a theoretical framework has been developed to systematically account for these contributions. The results demonstrate that criticality can serve as an effective amplifier of vacuum fluctuations, opening new avenues for probing and harnessing quantum critical ground states.
The quantum vacuum is not emptiness, but a tautly stretched string, where particles constantly appear and vanish. Abruptly changing conditions—like shifting the mirrors of a microcavity—causes the 'string' to emit real photons. Near a quantum phase transition, the critical point where matter's state changes abruptly, the effect intensifies. Even a tiny disturbance triggers an avalanche of photons flying at the speed of light. Thermal disorder usually silences quantum effects, but here it only whip-flicks the string, without quenching the glow. This gives rise to non-classical light, impossible with ordinary sources.
This opens the door to hypersensitive detectors and new emitters based on vacuum flashes. Spectroscopy—analyzing light by wavelength—reads quantum states like the sheet music of a vibrating string.
🎯 Quantum vacuum fluctuations are so real that they create a subtle attractive force between two closely spaced mirrors—the Casimir effect.