Large-angle twisted photonic crystal semiconductor nanolasers with ultra-low thresholds operating in the C-band

TL;DR

This paper reports the development of large-angle twisted photonic crystal nanolasers operating in the C-band, featuring ultra-low thresholds, small footprints, and tunable resonant wavelengths, advancing integrated photonic applications.

Contribution

It introduces a novel large-angle twisted photonic crystal nanolaser design with ultra-low thresholds and tunable modes, demonstrating practical room-temperature operation in the C-band.

Findings

Operates at room temperature with ultra-low threshold (~1.25 kW/cm^2)

Features an ultra-compact footprint (~25 μm^2) and small mode volume (0.47 (λ/n)^3)

Enables active tuning of resonant wavelength and optical modes

Abstract

Nanolasers, characterized by enhanced optical localization at subwavelength scale, have emerged as promising coherent light sources for ultra-compact, high-speed and energy-efficient photonic integrated circuits. Twisted photonic crystal nanocavity, constructed by stacking two layers of photonic crystal structure with a specified rotation angle, enables strong light confinement with an ultra-small mode volume and an extremely high quality factor. The twisted angle can be randomly selected, providing the possibility of actively tuning the resonant wavelength and optical mode distribution within a nanoscale twisted cavity. Here, we demonstrate large-angle twisted single-mode photonic crystal nanolasers operating in the C-band with an exceptionally ultra-compact footprint of approximately 25 $\mu m^2$ and an ultra-small mode volume of 0.47 $(\lambda/n)^3$. The reported twisted photonic crystal nanolasers are optically pumped at room temperature with an ultra-low threshold of $\sim$ 1.25 $kW/cm^2$. Our work provides a prospective method for easily constructing robust nanolasers by twisting angles, and paves the way for achieving high-performance nanoscale coherent light sources for densely integrated photonic chips.