2025/10/14 by Egor I. Kiselev, Kiselev, Egor I.
Physics and Astronomy · #Laser-Matter Interactions and Applications #Mechanical and Optical Resonators #Advanced Fiber Laser Technologies
paper · pdf · doi:10.48550/arxiv.2510.12990
We show how crystalline inversion symmetry can be dynamically broken by optical phonons with generic, hardening Kerr-like non-linearities. The symmetry-broken state is reached through a parametric instability that can be accessed by driving close to half the phonon resonance. After the onset of the instability, the system settles to a steady state with inversion-symmetry breaking phonon trajectories and strong second harmonic generation. The time averaged positions of the atoms are displaced relative to equilibrium, resulting in a ferroelectric rectification of the driving signal.