Continuous-wave operation of all-epitaxial InP-based 1.3 µm VCSELs with 57% differential quantum efficiency
All-epitaxial InP-based 1.3 µm VCSELs with a record-high continuous-wave differential quantum efficiency (57%) for single active region long-wavelength devices are demonstrated. Low-loss optical mode confinement is achieved through a selectively etched undercut tunnel-junction aperture. Singlemode continuous-wave lasing was observed up to 87°C and the room-temperature output power was 1.1 mW at a current of 4.1 mA and a wavelength of 1.305 µm.