The MQO group investigates fundamental physics and develops quantum applications with mesoscopic-sized quantum states of light, all underpinned by enabling technology. Mesoscopic quantum optical states comprise 10s, 100s and 1000s of nonclassically-distributed photons. From a fundamental perspective, they can be used to explore quantum physics at energy scales that are visible to the human eye. In addition, this scale is crucial for demonstrating a genuine quantum enhancement over classical schemes in many areas including metrology, computation and communication.
To study these systems, we use integrated optical circuits based on titanium in-diffused waguides in lithium niobate, in combination with superconducting detectors. This means that much of the nonlinear optical properties of lithium niobate must be re-optimised to function in a low-temperature environment.
In this context, the research of the MQO group can be divided into three interrelated areas: detector architectures for mesoscopic quantum optics, fundamentals of low-temperature nonlinear optics and device development for low-temperature integrated optical quantum technologies.