Tamura Marcus, Morison Hugh, Shastri Bhavin J
Department of Physics, Engineering Physics and Astronomy, Queen's University, Kingston, Canada.
Nanophotonics. 2022 May 2;11(17):4017-4025. doi: 10.1515/nanoph-2022-0077. eCollection 2022 Sep 2.
A mechanism for self-pulsation in a proposed graphene-on-silicon microring device is studied. The relevant nonlinear effects of two photon absorption, Kerr effect, saturable absorption, free carrier absorption, and dispersion are included in a coupled mode theory framework. We look at the electrical tunability of absorption and the Kerr effect in graphene. We show that the microring can switch from a stable rest state to a self-pulsation state by electrically tuning the graphene under constant illumination. This switching is indicative of a supercritical Hopf bifurcation since the frequency of the pulses is approximately constant at 7 GHz and the amplitudes initial grow with increasing Fermi level. The CMOS compatibility of graphene and the opto-electronic mechanism allows this to device to be fairly easily integrated with other silicon photonic devices.
研究了一种提出的硅基石墨烯微环器件中的自脉动机制。在耦合模理论框架中纳入了双光子吸收、克尔效应、饱和吸收、自由载流子吸收和色散等相关非线性效应。我们研究了石墨烯中吸收和克尔效应的电可调性。我们表明，在恒定光照下通过电调谐石墨烯，微环可以从稳定的静止状态切换到自脉动状态。这种切换表明存在超临界霍普夫分岔，因为脉冲频率在7GHz左右近似恒定，且振幅最初随费米能级的增加而增大。石墨烯的CMOS兼容性以及光电机制使得该器件能够相当容易地与其他硅光子器件集成。
