Threshold Characteristics of Slow-Light Photonic Crystal Lasers

TL;DR

This paper investigates the threshold behavior of slow-light photonic crystal lasers, revealing a minimum threshold gain at a specific cavity length due to slow-light effects and fabrication disorder, supported by experimental and theoretical analysis.

Contribution

It provides a combined experimental and analytical study of how slow-light influences laser thresholds and disorder effects in photonic crystal lasers.

Findings

Threshold gain has a minimum at a specific cavity length.

Longer lasers operate deeper into the slow-light regime.

Disorder-induced losses increase with slow-light effects.

Abstract

The threshold properties of photonic crystal quantum dot lasers operating in the slow-light regime are investigated experimentally and theoretically. Measurements show that, in contrast to conventional lasers, the threshold gain attains a minimum value for a specific cavity length. The experimental results are explained by an analytical theory for the laser threshold that takes into account the effects of slow-light and random disorder due to unavoidable fabrication imperfections. Longer lasers are found to operate deeper into the slow-light region, leading to a trade-off between slow-light induced reduction of the mirror loss and slow-light enhancement of disorder-induced losses.