Distillation of quantum squeezing

Squeezed states of various types of quantum oscillators are important nonclassical resources for quantum physics. We derive how much squeezing is universally distillable from multiple copies of non-Gaussian nonclassical states. We extend the approach to more efficient nonuniversal squeezing distillation, transforming hidden and scattered quantum nonclassicality to applicable squeezing. We demonstrate the distillation of squeezing from the mixtures of Gaussian states and also from quantum non-Gaussian states, incompatible with such the mixtures of Gaussian states.