A bulk optical isolator with high optical performance

Proposed in this paper is the design and demonstration of a novel compact isolator with high optical performance. Compared with traditional optical isolators, the proposed scheme has added four wave plates (WP) with certain phase-delay and polarization directions. With theoretical and experimental verifications, the fabricated device is demonstrated to achieve an isolation value of more than 40 dB covering a broad-band wavelength range of 300 nm in simulation, and exceeding 100 nm in measurement. Its temperature insensitive and low PMD characteristic also has been investigated. This isolator presents a new possibility for developing nonreciprocal devices in the field of optical communications.