Broadband single and multimode quantum light generation using optical nonlinearities

Abstract

There is a growing effort in many fields of physics to bridge the classical and quantum realms. To our best understanding, our world is governed by the laws of quantum mechanics, but some of its most interesting features - such as the ability to morph uncertainty and noise - are washed out when system sizes become too large. Light is the ideal playground to investigate the interplay between the classical and quantum domains, with its well-known particle-wave duality and diverse behaviors at both the classical wave and single photon levels. To this end, there is significant interest in generating quantum states of light that can be harnessed for applications in the classical world we are most familiar with. However, maintaining "quantumness'' as the number of photons grows large has proved challenging due to the detrimental effects of loss. In this thesis, I describe two theoretical proposals to make macroscopic quantum light a reality. I focus on bright intensity squeezed states of light that have intensity noise far below the standard quantum limit. If realized, these states would bring the quantum mechanical phenomenon of squeezing to macroscopic intensities, which in turn could pave the way towards widespread quantum light sources that offer enhanced signal to noise ratios. I describe two distinct methods that use tools from nonlinear optics and dissipation engineering to realize broadband squeezing in both single and multiple frequency modes. I show that the squeezing can be tunable across a wide range of the electromagnetic spectrum that spans frequencies where quantum light has never been generated.