Revelation and analysis of optical phase delay exhibited by Al-doped 4H-SiC due to current induction

Magneto-optical (MO) effect-based devices, such as spatial light modulators and optical isolators, have become increasingly prevalent in the fields of optical communication and information processing because of their high-speed response. However, conventional MO devices (e.g., Terbium Gallium Garnet crystals) have poor transparency in the visible range and polarization rotation capability, which constrains the integration of small optical systems. Recently, a silicon carbide spatial light modulator (SiC-SLM) (depicted in Fig. 1(a)) was developed via dressed-photon-phonon (DPP)-assisted annealing of 4H-SiC crystals doped with aluminum atoms [1]. This device exhibited an extremely large MO effect in the visible range, as evidenced by a Verdet constant of $9.51\times 10^{4}\text{rad}/\mathrm{T}\bullet \mathrm{m}$ near its absorption edge at 457 nm. There are many unknown aspects such as the spatial distribution of the degree of polarization rotation, optimal annealing conditions, and geometrical conditions of the electrode. In this study, the utilization of the SiC-SLM for spectral filtering of imaging technology and the photophysical properties of the SiC-SLM device, especially the phase delay by birefringence, were investigated, and this progress promises a new SLM application.