Frequency‐Dependent Squeezing via Einstein–Podolsky–Rosen Entanglement Based on Silicon Nitride Microring Resonators

Considerable efforts have been devoted to augmenting the performance of displacement sensors constrained by quantum noise, particularly within high‐precision applications such as gravitational wave detection. Frequency‐dependent squeezing methodologies have adeptly exceeded the standard quantum limit in optomechanical force measurements, catalyzing profound advancements in the field. Concurrently, notable strides in integrated photonics have paved the way for the realization of integrated Kerr quantum frequency combs (QFCs). In this work, a sophisticated platform designed for the creation of Einstein–Podolsky–Rosen (EPR)‐entangled QFCs utilizing on‐chip silicon nitride microring resonators is presented. This platform facilitates an exhaustive analysis and optimization of entanglement performance, establishing a robust framework for noise mitigation. By incorporating the quantum dynamics of Kerr nonlinear microresonators, the system accommodates at least 12 continuous‐variable quantum modes, including 6 pairs of concurrently EPR‐entangled states. Moreover, through precise tuning of the detection angle of the idler mode, the signal mode transitions into a single‐mode squeezed state. Harnessing the frequency‐dependent nature of this detection angle enables the achievement of frequency‐dependent squeezing. A comparative analysis under different dispersion conditions is also presented.