Kunihiro Hara

Novel Window-Structure AlGaInP Visible-Light Laser Diodes with Non-Absorbing Facets Fabricated by Utilizing GaInP Natural Superlattice Disordering

Window-structure AlGaInP visible-light ( λL=680 nm) laser diodes (LDs) have been fabricated, for the first time, by utilizing GaInP natural superlattice (NSL) disordering with selective Zn diffusion. The bandgap energy for the active layer near the mirror facets is increased by 70 meV by the NSL disordering. An 80 mW output power in a fundamental transverse-mode has been achieved for the uncoated window LDs under 1 µsec long pulsed operations. The maximum output power density for the window LDs is estimated to be 10 MW/cm2, which is five times higher than that for conventional LDs.

632.7 nm CW Operation (20?C) of AlGaInP Visible Laser Diodes Fabricated on (001) 6? off toward [110] GaAs Substrate

632.7 nm continuous wave operation was achieved at 20°C, by an AlGaInP visible laser diode (LD) with an AlGaInP quaternary active layer fabricated on a (001) GaAs substrate with a misorientation angle of 6° toward the [110] direction. The epitaxial layers for the laser structure are grown by metalorganic vapor phase epitaxy. The lasing wavelength is almost the same as that for He-Ne lasers. Lasing wavelengths for the LDs were also compared with wavelengths for those fabricated on an exact (001) orientation substrate.

30-mW 690-nm high-power strained-quantum-well AlGaInP laser

A high-power 690-nm AlGaInP laser for use in a high-density rewritable-optical-disk memory system is presented. The deterioration of its temperature characteristics, which results from the high-power-oriented laser structure, is improved by using compressively strained GaInP quantum wells as the active layer. Output power of 40 mW is achieved up to 80 degrees C. Stable fundamental-transverse-mode operation is obtained up to 50 mW. Output-power-induced facet degradation is suppressed by an Al/sub 2/O/sub 3/ facet coating. The lasers operate stably at 30 mW at 50 degrees C for over 2600 h. The mean extrapolated lifetime is 10000 h. >

Real index-guided AlGaInP visible laser with high-bandgap energy AlInP current blocking layer grown by HCl-assisted metalorganic vapor phase epitaxy

We establish selective area growth of Al/sub x/In/sub 1-x/P and develop a high power 685-nm real index-guided AlGaInP visible laser for the first time. This laser has a high-bandgap energy Al/sub 0.5/In/sub 0.5/P current blocking layer, which is selectively grown by HCl-assisted metalorganic vapor phase epitaxy (MOVPE). Threshold current is reduced and slope efficiency is improved, compared with conventional lasers with GaAs current blocking layers. The threshold current and slope efficiency for a real index guided AlGaInP laser are 36 mA and 1.0 W/A, with a cavity length of 710 /spl mu/m. Fundamental transverse mode operation up to 50 mW, and CW operation over 55 mW at 25/spl deg/C, without any kinks in the light output power versus current curve, are achieved. This laser is operated stably for more than 1000 hours at 30 mW constant output power, at 50/spl deg/C. >

High brightness and reliable AlGaInP-based light-emitting diode for POF data links

High brightness and reliability operation ring light-emitting diode (LED) is fabricated for plastic optical fiber (POF) link using the distributed Bragg reflector (DBR) mirror and antireflection (AR) coating. The ring LED exhibited optical output as high as 3.5 mW at the bias current of 100 mA. Furthermore, the projection lifetime is also estimated to be 1/spl times/10/sup 6/ h at a 35-mA data-link operating current and ambient temperature of 60/spl deg/C.

Reliability consideration for AlGaInP laser diodes by automatic power control aging simulation

We develop an automatic power control aging simulation method for AlGaInP visible light emission laser diodes and apply it to aging tests of 650 nm wavelength AlGaInP lasers. A laser degradation expression, on which the simulation is based, is derived from automatic current control tests for 680 nm lasers. The simulation results agree well with the experimental results. The simulation is then used to show laser reliability (operation lifetime) as a function of laser initial characteristics (threshold current, characteristic temperature and the maximum cw temperature).

30 mw 690 nm high-power strained-quantum-well AlGaInP laser with Al/sub 2/O/sub 3/-coated mirror facets

Abstract: 30-mW stable operation at 500C over 2,000 hours has been achieved for transverse-mode-stabilized 690-nm AlGaInp lasers by using Al/sub 2/O/sub 3/-coated mirror facets and a strained-quanturn-well active layer.

Real index guided AlGaInP visible laser with high bandgap energy AlInP current blocking layer grown by HCl-assisted metalorganic vapor phase epitaxy

Summary form only given. Selective growth of high bandgap energy AlInP layers were established by HCl-assisted MOVPE and applied to real index guided AlGaInP high power lasers for the first time. Reduction in threshold current and increase in slope efficiency were obtained. CW operation over 50 mW without any kinks was achieved.