A high power InGaAs/GaAsP vertical-cavity surface-emitting laser and its temperature characteristics

Abstract

A high power bottom-emitting InGaAs/GaAsP vertical-cavity surface-emitting laser with a large aperture (400 µm diameter) is described. The device has been fabricated by using oxidation confinement technology. The device threshold current is 610 mA, and the maximum output power is up to the watt regime (1.42 W) at room temperature (24 • C) with a pulse condition (pulse width of 50 µs, repetition rate of 1 kHz). The maximum continuous wave optical output power at room temperature is as high as 1.09 W. The lasing peak wavelength is 987 nm, the full width at half-maximum is 0.9 nm, and the far-field divergence angle is below 10 •. The temperature characteristics of the device are also obtained. A special temperature dependence of the threshold current in the vertical-cavity surface-emitting laser structure is observed; the characteristic temperature T 0 is over 220 K, and the wavelength shift with temperature is only about 0.06 nm K −1 .

High-Power Vertical-Cavity Surface-Emitting Laser under a Short Pulsed Operation

“…The VCSELs lase at a wavelength of 986 nm. The VCSELs with a current aperture diameter of more than 200 m have a higher external efficiency than those with a narrower current aperture, since thermal rollovers are not observed in curves of more than 200 m. This critical aperture size is smaller than previously reported for high power VCSELs under cw or long pulsed operations, 3,4) as the heat generation of our VCSELs is suppressed due to the relatively short pulsed operations. The threshold current density is over 3.1 kA/cm 2 , which is approximately the same value under long pulsed operations with a pulse width of several tens of s. This threshold current density is relatively high due to the resistance of the low-doped substrate.…”

“…A maximum output power of 1.95 W for cw and 1.42 W for pulsed operations with several tens s width were reported. 3,4) For these operations, the output power is limited by thermal rollover caused by Joule heat, and thus these devices have low thermal resistances with large active diameters of over 400 m. 3,4) In LIDAR, a time frame of several tens of ns and a repetition rate of a few kHz are enough to detect objects. Such short pulsed operations with infrequent repetition tend to inhibit the thermal rollover caused by joule heating.…”

Vertical-cavity surface-emitting lasers with periodic gain structure

“…High-power VCSELs with conventional threeQWs structure has been reported in our previous paper [13]. The characteristics of the VCSELs with three-QWs and periodic gain structure are compared in Table 1.…”

High-Pulsed-Power (49W) Vertical-Cavity Surface-Emitting Laser with Five Quantum Wells by Uniform Current Injection into Large Emitting Area

“…Therefore a single emitter VCSEL with an output power of over 10 W, which is the typical output power of LIDAR, is needed. The output power of a single emitter VCSEL is limited by thermal rollover caused by Joule heat, so a high power single emitter VCSEL needs to have a low thermal resistance with a large active diameter over 100 µm and a bottom-emitting structure [4,5,6]. Previously, we reported the maximum output power of 12.5 W was achieved by a single VCSEL with five quantum well under a pulsed operation with a pulse width of 50 ns and a repetition rate of 1 kHz [7].…”