Semiconductor nanoring lasers

Lasing in a subwavelength metal-clad nanoring resonator has been demonstrated with a tunable emission wavelength, controlled by the width of the ring. The emission wavelength is shown to be tunable within a 10 nm wavelength range by changing the ring width between 240 and 340 nm. This property is expected to mitigate a common nanolaser problem of fine-tuning the emission wavelength without significantly changing the laser dimensions.