High-Temperature Continuous-Wave Single-Mode Operation of 1.3-$\mu$m p-Doped InAs–GaAs Quantum-Dot VCSELs

In this letter, we have demonstrated continuous-wave single-mode operation of 1.3-$\mu{\hbox {m}}$ InAs–GaAs quantum-dot (QD) vertical-cavity surface-emitting lasers (VCSELs) with p-type modulation-doped QD active region from 20 $^{\circ}\hbox{C}$ to 60 $^{\circ}\hbox{C}$ . The highest output power of 0.435 mW and lowest threshold current of 1.2 mA under single-mode operation are achieved. The temperature-dependent output characteristics of QD-VCSELs are investigated. Single-mode operation with a sidemode suppression ratio of 34 dB is observed at room temperature. The critical size of oxide aperture for single-mode operation is discussed.