Nonlinear interferometry-based metrology of magneto-optical properties at infrared wavelengths

Magneto-optical properties of materials are utilized in numerous applications both in scientific research and industry. The novel properties of these materials can be further investigated by performing metrology in the infrared wavelength range, thereby enriching their potential applications. However, current infrared metrology techniques can be challenging and resource-intensive due to the unavailability of suitable components. To address these challenges, we propose and demonstrate a set of measurements based on nonlinear interferometry, which allows us to investigate magneto-optical properties of materials at infrared wavelength range by performing optical detection at the visible range. For a proof-of-principle study, we measure the Verdet constant of a bismuth iron garnet crystal, over a spectral bandwidth of 600 nm in the near-infrared range.