  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.
