Masato TAKIGUCHI, Ph. D.

Top page   Biography   Research   Publication   Conference   Domestic   Others

My Interests

    Nano laser and nano emitter, Cavity quantum electrodynamics (cavity QED)
    Photonic nanostructure, Quantum optics, Laser spectroscopy

All-optical switching with nanowires on Si photonic crystal

    We report the successful demonstration of all-optical switching using a sub-wavelength InP/InAsP nanowire on a silicon photonic crystal at telecom wavelength [Takiguchi, et. al., ACS photonics 2020, Supplementary Journal Cover]. In this work, we employ two different hybrid nanowire cavities (L3 type and The line defect type). The line defect photonic crystal cavity with a nanowire shows the highest Q-factor ~ 25000. The switching time is obtained 150 ps and it is the fastest in nanowire switches.


High speed operation of telecom-band single nanowire LED on Silicon

    High speed operation of a current injection p-i-n InAs/InP nanowire at telecom band is important for future on-chip signal processing. In this study, we explore a telecom-band single nanowire light-emitting diode (LED) on Si and demonstrated the dynamic properties. The nanowire LED shows Gbps modulation and clear eye pattern [Takiguchi, et. al., APL 2018]. We believe that our NW-LED represents a major step in the development of an on-chip light source.


CW operation of telecom-band nanowire photonic crystal laser

    We demonstrate an InAsP/InP single-nanowire telecom-band CW laser (diameter ~100 nm) on Si photonic crystal platform for the first time. Using this laser, we measure 10 Gbit/s signal modulation using a SSPD and a TCSPC module and obtain clear opened eye-diagram by superimposing the averaged PRBS data over a specific time period [Takiguchi, et. al., APL photonics 2017]. About this result, NTT and AIP have sent out a press release [NTT press release, AIP Journals in the News].

Fast & High β embedded MQW photonic crystal laser

    We study spontaneous emission control and lasing oscillation of embedded multiple quantum well (MQW) in InP photonic crystal nanocavities. We observed large emission rate ratio between the on- and off-resonant conditions (30:1). This is the highest ratio reported for MQW nano-laser[Takiguchi, et. al., APL 2013] . By adopting high β embedded multiple quantum well photonic crystal nanocavities, we have also demonstrated smooth-lasing transition, which indicates thresholdless-like lasing theoretically predicted, by mean of L-L curve analysis, linewidth analysis, and photon correlation measurements[Takiguchi, et. al., OE 2016].