Squeezing induced by spontaneous rotational symmetry breaking

This communication studies the phenomenon of quadrature squeezing generated via spontaneous rotational symmetry breaking. A degenerate optical parametric oscillator (DOPO) tuned to the first family of transverse modes at the signal frequency, and having perfectly spherical mirrors. When pumped above threshold with a Gaussian beam and within a classical description, it is easy to show that a TEM₁₀ mode with an arbitrary orientation emerges at the subharmonic, hence breaking the rotational symmetry of the system in the transverse plane.