| Research Abstract |
1.Selective area growth mechanism in metal organic vapor phase epitaxy integration : Concerning the selective area MOVPE growth which forms the basis of monolithically integrated photonic circuits fabrication, we experimentally obtained selective growth thickness profiles of InP and GaAs, and extracted important parameters such as sticking probability and diffusion constants by comparing the experimental profiles with two dimensional simulation profiles. These parameters enable computer-aided design of photomasks in photonic integrated circuits (PICs) through the simulation of selective area growth.
2.Mach-Zehnder optical switch circuit incorporating bulk InGaAsP/InP high-mesa waveguides : We investigated Mach-Zehnder interferometer optical switch circuits with high-mesa waveguide structure utilizing Franz-Keldysh effect in bulk InGaASP on InP substrates. We established methane-hydrogen cyclic reactive ion beam etching technique, and made fabrication of the high-mesa waveguides possible
… More
. Devices were then fabricated by using the etching technique and an electron beam lithography. Consequently, switching voltage as low as 3V was achieved over a wavelength range of 1.53-1.56 μm independent of polarization. The product of the phase modulation region length and the switching voltage is 1.5V mm, which is four times better than previous reports.
3.Design and fabrication of integrated all-optical witch circuits se he selective re growth and multimode interference (MMI) devices : The selective area MOVPE above has been utilized to integrate semiconductor optical amplifiers, MMI couplers, and input/output waveguides on InP substrates, and thereby all-optical switch circuits were fabricated. Extinction ratio was improved in an optical switching experiment by control light.
4.All-optical wavelength conversion circuit based on photo-induced refractive index change in electro-absorption (EA) optical modulators : By utilizing polarization dependence of photo-induced refractive index change in EA modulators, we demonstrated all-optical wavelength conversion with a very simple configuration consisting of an EA modulator and a polarizer.
5.Study on wavelength assigned photonic switching system : We proposed "wavelength assigned photonic switching system (WAPS)" as a method of optical switching in photonic networks utilizing photonic integrated circuits, and studied its transmission characteristics as well as its applicability to IP networks. Less
|
