2023/10/24 by Ioannis Petrides, Jonathan B. Curtis, Petrides, Ioannis +7 · 1 citation
Computer Science · Engineering · Physics and Astronomy · #FOS: Physical sciences #Mechanical and Optical Resonators #Mesoscale and Nanoscale Physics (cond-mat.mes-hall) #Optics (physics.optics) #Photonic and Optical Devices #Quantum Information and Cryptography #Quantum Physics (quant-ph)
paper · pdf · doi:10.48550/arxiv.2310.16174
openalex publication_date 2023/10/24 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Reciprocal and nonreciprocal effects in dielectric and magnetic materials provide crucial information about the microscopic properties of electrons. However, experimentally distinguishing the two has proven to be challenging, especially when the associated effects are extremely small. To this end, we propose a contact-less detection using a cross-cavity device where a material of interest is placed at its centre. We show that the optical properties of the material, such as Kerr and Faraday rotation, or, birefringence, manifest in the coupling between the cavities' electromagnetic modes and in the shift of their resonant frequencies. By calculating the dynamics of a geometrical photonic state, we formulate a measurement protocol based on the quantum metric and quantum process tomography that isolates the individual components of the material's complex refractive index and minimizes the quantum mechanical Cramér-Rao bound on the variance of the associated parameter estimation. Our approach is expected to be applicable across a broad spectrum of experimental platforms including Fock states in optical cavities, or, coherent states in microwave and THz resonators.