Środowiskowe Seminarium z Informacji i Technologii Kwantowych

Quantum states of light featuring high-dimensional entanglement are of growing interest as a platform for quantum information processing. Furthermore, complex optical states with non-Gaussian phase space distributions have been shown to be a vital resource for optical quantum simulation and computation. Multimode squeezed vacuum, a useful resource for preparing such states, can be generated experimentally using parametric downconversion of a broadband optical frequency comb in a synchronously-pumped optical parametric oscillator (SPOPO). I will expand on how we can achieve a high degree of control over the mode structure of the quantum light at the SPOPO output by shaping the pulse train used to pump the SPOPO, as well as the techniques we have developed to characterise these states, including spectrally multipixel homodyne detection. I will also describe how conditional single-photon subtraction enables us to use multimode squeezed vacuum as a resource for preparing non-Gaussian states.