TM mode waveguide isolator monolithically integrated with InP active devices

Abstract

We propose and experimentally demonstrate a novel structure for monolithically integrating a TMmode waveguide optical isolator with active InP devices. A semiconductor ring laser with integrated isolator is fabricated and demonstrated for the first time.I.

Reduced Threshold Current and Enhanced Extinction Ratio in a Magnetically Controllable Fe50Co50–InGaAlAs/InP Nonreciprocal Semiconductor Laser

“…Reduced threshold current and enhanced modal gain also contribute to larger extinction ratio in magnetically controllable nonreciprocal semiconductor lasers owing to the Fabry-Perot resonance effect, and in unidirectional ring lasers owing to the resonant ring cavity effect. 28) Fig. 2.…”

“…27) Unidirectional semiconductor ring lasers (SRLs) utilizing nonreciprocal semiconductor lasers have been realized. 26,28,29) Fig. 1.…”

“…26) In an Fe/Ni-InGaAsP/InP unidirectional ring laser with a radius of 500 m and a semiconductor optical isolator length of 500 m, the threshold current was reported to be 170 mA. 28) In terms of the choice of the ferromagnetic metal, it was reported that Fe 50 Co 50 shows the largest magneto-optic effect at a wavelength of 1300 nm. 10) Therefore, optimization of the layer structures and ferromagnetic metals is important for improving the performance of nonreciprocal semiconductor lasers and unidirectional ring lasers.…”

Demonstration of a Magnetically Controllable Fabry–Perot Laser and an Unidirectional Ring Laser Utilizing a Nonreciprocal Semiconductor Optical Amplifier

“…3) The extinction ratio of 14.7 dB/mm corresponds to 0.147 dB/10 m, which is sufficient for realizing unidirectional lasing. 17) In summary, we have reported on the photon density redistribution in nonreciprocal semiconductor optical amplifiers. The fabricated nonreciprocal semiconductor optical amplifiers exhibited Fabry-Perot lasing whose intensity was modulated by the magnetization direction, and the extinction ratio was 1.9 dB.…”

TE-mode nonreciprocal propagation in passive Fe50Co50–InGaAsP/InP semiconductor optical isolators

“…The ring radius and length of the semiconductor optical isolator are both 500 µm, and the threshold current is 170 mA. 32) It was reported that the amount of optical isolation for TM-mode unidirectional ring lasing is 0.5 dB in the ring cavity with a Y-branch coupler, on the basis of an analysis using Lamb equations in the ring cavity. 33) We have analyzed the amount of optical isolation for TE-mode unidirectional lasing in the ring cavity composed of ring radius r = 100 µm, a 120-µm-long semiconductor optical amplifier, and an 80-µm-long semiconductor optical isolator by using Lamb equations, and found that the amount of optical isolation is 0.16 dB in an 80-µm-long (2.0 dB/mm) semiconductor optical isolator, where the directional coupler was designed so that 10% of light in the ring cavity is coupled to the output waveguide.…”