Maria Chekhova
Max-Planck Institute for the Science of Light, Germany
Title: Nonlinear interferometer for shaping the spectrum of bright squeezed vacuum
Biography
Biography: Maria Chekhova
Abstract
Bright squeezed vacuum is a macroscopic state of light featuring non-classical properties, from photon-number entanglement and quadrature squeezing to the violation of certain types of Bell’s inequalities. By producing this state of light through high-gain parametric down-conversion in two coherently pumped crystals, one obtains a nonlinear interferometer, which offers various interesting possibilities. Among others, this is shaping the bright squeezed vacuum in space/angle and time/frequency, with the ultimate goal being to achieve a single-mode state. Moreover, this single mode can be of any desired shape, both in space and time. In our recent experiments, we have achieved generation of bright squeezed vacuum with a single spatial mode by spatially separating the two crystals forming the nonlinear interferometer. This mode had Gaussian shape but under certain conditions, spatial modes with non-zero optical angular momentum could be also obtained. By completing the nonlinear interferometer with a dispersive medium placed inside it, we achieved the generation of bright squeezed vacuum with only 1.5 frequency modes. The obtained single-mode bright squeezed vacuum can be used for various applications such as conditional preparation of non-Gaussian states, sensitive quantum phase measurements, and enhanced nonlinear optical effects.