Semiconductor DFB laser with plasmonic metal layers for subwavelength confinement of light

An InP-based 1.55-μm wavelength DFB laser that uses surface plasmon polaritons for light confinement is proposed. A threshold current of 650 μA can be expected with the waveguide width of 200 nm and the cavity length of 76.5 μm. The device is monolithically integratable with waveguide-based optical devices.