Increasing the Quality Factor (Q) of 1D Photonic Crystal Cavity with an End Loop-Mirror

Abstract

Increasing the quality factor (Q) of an optical resonator device has been a research focus to be utilized in various applications. Higher Q-factor means light is confined in a longer time which will produce a shaper peak and higher transmission. In this paper, we introduce a novel technique to increase further the Q-factor of a one-dimensional photonic crystal (1D PhC) cavity device by using an end loop-mirror (ELM). The technique utilizes and recycles the light transmission from the conventional 1D PhC cavity design. The design has been proved to work by using the 2.5D FDTD simulation with Lumerical FDTD and MODE softwares. By using the ELM technique, the Q- factor of a 1D PhC design has been shown to have increased up to 79.53 % from the initial Q value without the ELM. This novel design technique can be combined with any high Q-factor and very high Q-factor designs to increase more the Q-factor value of a photonic crystal cavity devices or any other suitable optical resonator devices. The experimental result shows that the device is measurable by adding a Y-branch component to the one-port structure and able to get the high-Q result.

Reflection Mirrors, Optical Gyroscopes, Filters, and Wavelength Interleavers Based on Sagnac Interference in Integrated Photonics

“…Recently, by engineering backscattered light from the microresonator to the pump laser cavity, turnkey soliton microcomb generation without the need of complex startup protocols and feedback control circuitry has been realized [382]. The Q factor enhancement of resonant cavities achieved by exploiting Sagnac interference [56,187,238,239] can be employed for implementing low-linewidth lasers, high-sensitivity sensors, and high-efficiency nonlinear optical devices. Given the bulky size and complex structure of state-of-the-art microscopy systems based on Sagnac interference [392][393][394], integrated Sagnac interference devices hint at the implementation of miniatured microscopy systems with reduced SWaP.…”

Integrated photonic chips based on Sagnac interference

“…Up to 11-times enhancement of the Q factor and 8-dB improvement in the extinction ratio were achieved for the fabricated device. The enhancement of the Q factor of a silicon 1D-PhC cavity has also been realized by connecting an integrated SLRM (Figure 17(b)) [239], where the light reflected back from the SLRM was recycled by the 1D-PhC cavity to enable the Q factor enhancement. The theoretically estimated increase in the Q factor compared to the device without the SLRM was up to ~79.5%.…”

“…Recently, by engineering backscattered light from the microresonator to the pump laser cavity, turnkey soliton microcomb generation without the need of complex startup protocols and feedback control circuitry has been realized [372]. The Q factor enhancement of resonant cavities achieved by exploiting Sagnac interference [56,187,238,239] can be employed for implementing low-linewidth lasers, high-sensitivity sensors, and high-efficiency nonlinear optical devices. Given the bulky size and complex structure of stateof-the-art microscopy systems based on Sagnac interference [373][374][375], integrated Sagnac interference devices hint at the implementation of miniatured microscopy systems with reduced SWaP.…”