Jones-matrix dual-comb spectroscopic polarimetry
Spectroscopic polarimetry (SP) is a powerful tool for evaluation of thin film, optical materials, and biological samples because it can provide both polarimetric and spectroscopic characteristics of objects. However, its performance is often hampered by the mechanical instability and the limited data acquisition speed arising from the mechanical polarization modulation. Dual-comb spectroscopic polarimetry (DCSP) based on a combination of SP with dual-comb spectroscopy can acquire optical spectra of amplitude ratio and phase difference in p- and s-polarization components of the output light from simultaneous measurement of optical spectra of optical amplitude and phase in p- and s-polarization components without the need for mechanical polarization modulation. In this article, we combine the DCSP with polarization control pulse sequences (PCPS) with different polarizations and time delays for a more detailed analysis of the sample's polarization response based on Jones matrix. We obtain Jones matrix of a sample as a function of wavelength by measuring those optical spectra while multiplexing the incident light into multiple polarizations instead of a single polarization. Such Jones matrix DCSP (JM-DCSP) is applied for analysis of optical elements with known polarization property and its experimental result is in good agreement with theoretical values, indicating the validity of the proposed method. JM-DCSP will further expand the application scope of SP.