Theory of high-speed nanolasers and nanoLEDs

Abstract

We investigate the intrinsic high speed modulation responses of nanolasers and nanoLEDs using bulk, quantum wells (QWs), and quantum dots (QDs) based on a rigorous rate-equation model, which incorporates the optical energy confinement factor to properly account for the negative permittivity and dispersive metal plasma property. We then investigate the dependence of the bandwidth and the energy per bit on the quality factor and the normalized optical volume. We find out that the conditions for the energy per bit less than 50 fJ/bit and 10 fJ/bit are the normalized optical modal volume less than 20 and 5, respectively. In addition, with a uniform quantum dot size in a nanocavity, quantum-dot metal-cavity nanolasers exhibit the largest bandwidth among three types of active materials, and a low energy per bit. With their insensitivity to temperature, quantum-dot metal-cavity nanolasers are favorable for future high speed light sources.