Methodological investigation into the noise influence on nanolasers' large signal modulation

TL;DR

This paper investigates how intrinsic noise affects the large-signal modulation capabilities of nanolasers, emphasizing the importance of high pump rates for achieving significant bandwidths and guiding future technological improvements.

Contribution

It introduces a methodology for analyzing noise effects on nanolaser modulation and demonstrates the importance of high pump values for optimal performance.

Findings

Large pump values enable higher modulation bandwidths.

Low bias operation is limited by noise and bandwidth constraints.

Performance can surpass microdevices with increased pump rates.

Abstract

Nanolasers are considered ideal candidates for communications and data processing at chip-level thanks to their extremely reduced footprint, low thermal load and potentially outstanding modulation bandwidth, which in some case has been numerically estimated to exceed hundreds of GHz. The few experimental implementations reported to date, however, have so-far fallen very short of such predictions, whether because of technical difficulties or of overoptimistic numerical results. We propose a methodology to study the physical characteristics which determine the system's robustness and apply it to a general model, using numerical simulations of large-signal modulation. Changing the DC pump values and modulation frequencies, we further investigate the influence of intrinsic noise, considering, in addition, the role of cavity losses. Our results confirm that significant modulation bandwidths can be achieved, at the expense of large pump values, while the often targeted low bias operation is strongly noise- and bandwidth-limited. This fundamental investigation suggests that technological efforts should be oriented towards enabling large pump rates in nanolasers, whose performance promises to surpass microdevices in the same range of photon flux and input energy.