Zero-cell photonic crystal nanocavity laser with quantum dot gain

TL;DR

This paper reports the demonstration of a zero-cell photonic crystal nanocavity laser with quantum dot gain, achieving high quality factor and low threshold, advancing nanolaser design and efficiency.

Contribution

It introduces a zero-cell nanocavity design with high Q factor and low threshold, showing improved performance over traditional L3-type nanocavities.

Findings

Cavity quality factor of ~33,000 achieved

Zero-cell nanolasers have thresholds about one-third of L3-type

Higher Purcell factor correlates with lower laser threshold

Abstract

We demonstrate laser oscillation in a hexagonal-lattice photonic crystal nanocavity using an InGaAs quantum dot gain material by optical pumping at 5 K. The cavity comprises a defect created by shifting several air holes in a two-dimensional photonic crystal slab structure without removing any air holes to achieve both small mode volume and a high cavity quality factor. The measured cavity quality factors and estimated mode volume for the nanocavity are ~33,000 and ~0.004 um^3. The laser threshold is compared between the zero-cell and L3-type nanocavity lasers, and the zero-cell nanolasers are found to have small thresholds of about one-third of the L3-type nanolasers. This result suggests that a higher Purcell factor of the zero-cell nanolaser is reflected as a smaller laser threshold.