High Side-Mode Suppression Ratio with a Vernier effect Single-mode Laser Using Triple Coupled Microrings

Abstract

The development of single-mode lasers with a high side-mode suppression ratio (SMSR) is challenging but highly desirable for integrated photonics devices and long-distance communications due to its high spectral purity and stability. Here, we demonstrate a single-mode laser with a high side-mode suppression ratio based on size-mismatched triple coupled microrings. With the exact engineering of several key parameters of the structure like air gap and radii of microrings for controlling the free spectral range (FSR), a predominant mode is selected to lase in amplified spontaneous emission (ASE) of the gain material and all side and high order modes are suppressed by Vernier effect. In this work, we show that a single-mode operation is efficiently generated with an improved side-mode suppression ratio of over 20 dB in a three-ring-coupled microcavity laser. The single frequency output persists for a wide power range. The theoretical calculations and numerical simulations’ results confirm the validity of the experimental results. Our structural engineering creates new opportunities in a variety of frontier applications in single-mode lasers and high quality sensors.

Flatband slows down polariton dynamics in strongly coupled cavities

“…Furthermore, inter-cavity polaritons open up the quantum tomography protocols for local and independent measurements of the photonic and molecular degrees of freedom. Up until now, the exploration of strongly coupled photonic cavities has primarily centered around photonic crystal cavities [33], micro-rings [34], and whisperinggallery modes [35]. In the context of semiconductor microcavities, double-well potentials have led to the realization of phenomena like Josephson oscillations and self-trapping with intercavity polaritons, [36,37] and 2 have been recently proposed for quantum chemistry control [38] .…”