Abstract

Because of their reduced size, the operation of nanoscale lasers radically differs from that of conventional laser sources. For instance, the fraction β of spontaneous emission in the useful mode may be of the order of few 10⁻¹, in contrast to conventional lasers with β of the order of 10⁻⁵. As a consequence, the number of photons at threshold (equal to β^−1/2) is very small, typically 1 to 10. This has a strong impact on the laser characteristics. For such small numbers, fluctuations are large (of the order of the average values), occur only in integral multiples of a base value (corresponding to a change of a single unit), are asymmetric (as excursions into negative values are impossible) and cause the nanolaser output to deviate from that predicted by the traditional laser rate equations.

© 2015 IEEE