Subwavelength Nanowire Lasers on a Silicon Photonic Crystal Operating at Telecom Wavelengths

Here we report the successful demonstration of lasing 'oscillation in a subwavelength semiconductor nanowire (100 nm in diameter) at telecom wavelengths. Although a subwavelength nanowire is too thin to configure an efficient optical cavity by itself, we have combined the nanowire with a Si photonic crystal to form a nanowire-induced hybrid nanocavity. This unique configuration enables us to realize an efficient nanowire-based nanolaser on a Si platform. Our systematic study, which included L-L characteristics, emission wavelength, emission line width, emission lifetime, and photon correlation, has unambiguously revealed the lasing operation of the nanowire at 4 K. In addition, we have succeeded in changing the laser oscillation wavelength by moving the nanowire through a trench in the photonic crystal, which reveals the unique feature of this hybrid nanocavity. This is the first demonstration of telecom band subwavelength nanowire lasers, which may also be important for Si photonics applications.