Using superconducting elements to explore the oscillatory Unruh effect and to obtain entangled photon pairs produced from the vacuum

Title: Using superconducting elements to explore the oscillatory Unruh effect and to obtain entangled photon pairs produced from the vacuum

Abstract: Utilizing microwave superconducting cavities and other superconducting elements, we propose analog and actual schemes to realize the oscillatory Unruh effect (UE). The UE predicts that an accelerated photodetector moving in free space vacuum would experience thermal, blackbody radiation at a temperature proportional to the detector’s acceleration. For the oscillatory UE, we consider the mechanically oscillating photodetectors with the internal degree of freedom modeled as an oscillator and as a two level system (TLS), respectively. The photodetectors are coupled to a confined microwave cavity mode; when the sum of the cavity and detector frequencies is in resonance with the mechanical oscillating frequency, the resulting photon pair production rate from the vacuum is greatly enhanced. In the two proposed analog schemes, we utilize the breathing mode of the “film bulk acoustic resonator” (FBAR) for a close analogue of the center of mass oscillatory acceleration of a photodetector. In our proposed scheme to realize the actual oscillatory UE, we consider N>>1 oscillating center of mass detectors modeled as TLSs that are coupled to the cavity mode. The cavity mode accelerating photodetector system maps onto a parametrically driven Dicke-type model and when the detector number N exceeds a critical value, the photon production undergoes a phase transition from a normal phase to a superradiant-like, inverted lasing phase in which the average photon number is significantly enhanced such as to be potentially measurable.

Biography: Hui Wang is a postdoc researcher at RIKEN in Japan. She earned her Ph.D. in Physics with a thesis on using superconducting elements to explore the oscillatory Unruh effect from Dartmouth College in March 2021, under the supervision of Miles Blencowe. Upon its completion, she continued in Dartmouth College as a postdoc researcher. In June. 2022 she joined RIKEN as a postdoc researcher in the Theoretical Quantum Physics Laboratory led by Franco Nori. Her recent research focues on operational measurement procedures in quantum reference frames and converting virtual photons to real ones.