Upham Jeremy, Inoue Hiroki, Tanaka Yoshinori, Stumpf Wolfgang, Kojima Kazunobu, Asano Takashi, Noda Susumu
Opt Express. 2014 Jun 30;22(13):15459-66. doi: 10.1364/OE.22.015459.
We develop a gallium arsenide (GaAs) photonic crystal nanocavity device capable of capturing and releasing a pulse of light by dynamic control of the Q factor through free carrier photoexcitation. Unlike silicon-based devices where the performance of this dynamic optical control is limited by absorption from free carriers with nanosecond-order lifetimes, the short carrier lifetime (∼ 7 ps) of our equivalent GaAs devices enables dynamic control with negligible absorption losses. We capture a 4 ps optical pulse by briefly cycling the Q factor from 40,000 to 7900 and back just as the light couples to the nanocavity and confirm that the captured energy can be subsequently released on demand by a second injection of free carriers. Demonstrating dynamic control with negligible loss in a GaAs nanophotonic device also opens the door to dynamic control of cavity quantum electrodynamics with potential application towards quantum information processing.
我们开发了一种砷化镓（GaAs）光子晶体纳米腔器件，该器件能够通过自由载流子光激发对品质因数进行动态控制，从而捕获和释放光脉冲。与基于硅的器件不同，在硅基器件中这种动态光学控制的性能受到具有纳秒级寿命的自由载流子吸收的限制，而我们等效的GaAs器件的短载流子寿命（约7皮秒）使得能够在吸收损耗可忽略不计的情况下进行动态控制。我们通过在光耦合到纳米腔时将品质因数从40,000短暂循环到7900然后再返回，捕获了一个4皮秒的光脉冲，并确认随后可以通过再次注入自由载流子按需释放捕获的能量。在GaAs纳米光子器件中以可忽略的损耗展示动态控制，也为腔量子电动力学的动态控制打开了大门，这在量子信息处理方面具有潜在应用。
