The University of Tokyo · 공학
Takenaka 교수의 연구실은 광학적 비트 저장 및 스위칭 기반의 고속 신호 처리를 위한 반도체 레이저 및 파장 분할 다중화 기반 광 집적 회로 기술을 핵심으로 합니다. 특히 다중 모드 간섭을 이용한 모든 광학적 플립플롭, 저손실 고굴절률 대비 파이버 웨이브가이드, 그리고 III-V/Si 하이브리드 광소자 설계에 초점을 맞추고 있으며, 광메모리, 자가루팅, 고속 광신호 처리 등 미래 광통신 시스템의 핵심 소자 개발을 목표로 하고 있습니다.
표시된 성과는 수집된 데이터 기준으로 산출되며, 일부 차이가 있을 수 있습니다.
All-optical flip-flop operation of multimode interference bistable laser diodes (MMI-BLDs) was experimentally demonstrated for the first time. The MMI-BLD was prepared with a conventional ridge waveguide laser diode fabrication procedure, suitable for photonic integrated circuits. Bistable switching via two-mode bistability was obtained with approximately 0-dBm input powers due to cross-gain saturation and the saturable absorbers. Bit-length conversion was successfully obtained with noninverted
We have investigated the dark current of a germanium (Ge) photodetector (PD) with a GeO₂ surface passivation layer and a gas-phase-doped n+/p junction. The gas-phase-doped PN diodes exhibited a dark current of approximately two orders of magnitude lower than that of the diodes formed by a conventional ion implantation process, indicating that gas-phase doping is suitable for low-damage PN junction formation. The bulk leakage (Jbulk) and surface leakage (Jsurf) components of the dark current were
We proposed a novel InP based photonic wire waveguide with an InAlAs oxide cladding. The InGaAsP/InAlAs-oxide structure in the vertical direction provides an ultrahigh index contrast waveguide, and it allows a bend radius of a few mum with no vertical leakage loss. The InP photonic wire waveguide with a 500x300-nm rectangular channel core (refractive index n ~ 3.36) and an InAlAs oxide cladding (n ~ 2.4) was numerically analyzed using the three-dimensional time-domain beam propagation method (3D
We propose a novel bistable laser diode (BLD) with active multimode interference (MMI) cavity. Bistable switching can be realized between two cross-coupled modes by means of gain saturation. Static characteristics of the multimode interference (MMI)-BLD are analyzed using a finite-difference beam propagation method. The photon-carrier interactions are calculated using the carrier-rate equation. This model gives accurate distributions of photon and carrier densities, optical gain, and refractive
We present a novel optical phase modulation scheme on a Si photonic platform that uses a III-V/Si hybrid metal-oxide-semiconductor (MOS) capacitor formed by bonding an n-type InGaAsP membrane on a p-type Si waveguide. We numerically revealed that the phase modulation efficiency was improved by a factor of 7-8 owing to electron accumulation at the InGaAsP MOS interface when the n-type Si layer in a Si MOS optical phase shifter was replaced by an n-type InGaAsP layer. To realize the III-V/Si hybri
