Electrically pumped epitaxially regrown λ > 2 μm GaSb-based photonic crystal surface emitting lasers.

Photonic crystal surface emitting lasers (PCSELs) with wavelength up to 2.75 mu m have been designed and fabricated within III-V-Sb material system. A high-index-contrast photonic crystal layer was incorporated into the diode and cascade diode laser heterostructures by air-hole-retaining epitaxial regrowth. Transmission electron microscopy studies demonstrated uniform and continuous regrowth of the nano-patterned GaSb surface with AlGaAsSb alloy until air-pockets start being formed. The electrically pumped PCSELs generated narrow spectrum low divergence beams with mW-level output power. The diode PCSELs emitting near 2 mu m operated in continuous waver regime at low temperatures. The angle-resolved electroluminescence analysis demonstrated well resolved photonic subbands corresponding to Gamma(2) point of square lattice and photonic gaps of several meV.