Radiative optical isolator and circulator

A novel radiative optical isolator and a circulator are discussed in this paper. It is numerically estimated that with /spl lambda/=1.3 /spl mu/m, 45-dB isolation ran be achieved with an isolator of 8 mm in length. For a 21.5-mm-long 4-port circulator, the achievable isolation is about 45 dB, with approximately 1-dB insertion loss.