
The realization of quantum optomechanical Stimulated Ramann Adiabatic Passage (STIRAP) requires the exploration and fabrication of many different materials and devices. Specifically, we would like to create photonic devices with high-quality capabilities at sub-mK temperatures. Due to their inability to retain heat, superfluids are a desirable material to include in the fabrication of these devices. First, a number of different designs of photonic devices must be tested via computer simulations in COMSOL in order to find optimal parameters for our purposes. Moving toward simulations that resemble what we would ultimately like to fabricate and test experimentally, the equations required to simulate superfluids in COMSOL’s Equation Based Modeling feature were derived and implemented. Aside from the delicate fabrication process, another important part of quantum STIRAP is the detection of photon-phonon entangled pairs, for which a filter system is being developed at Universiteit Leiden in the Netherlands. The system is composed of eight mirrors that form four filter cavities designed to detect a single photon from the interaction between the pump light and a modulating membrane. Holding each of the four filter cavities at the resonant frequency of the reference cavity simultaneously requires precision within the order of a few picometers, for which a controller, called a ‘lock box’ is needed. Design and creation of these lock boxes was executed in the Kamerlingh Onnes National Laboratorium at Universiteit Leiden, and a neural network developed by Kellan Colburn (another collaborator of the Bouwmeester Group) was used to guide the locking. It was found that the box is able to lock fast and precisely, with a low signal to noise ratio coming into and out of the system.