High-power laser diodes based on asymmetric separate-confinement heterostructures

Asymmetric separate-confinement laser heterostructures with ultrawide waveguides based on AlGaAs/GaAs/InGaAs solid solutions, with an emission wavelength of ～1080 nm, are grown by MOCVD. The optical and electrical properties of mesa-stripe lasers with a stripe width of ～100 μm are studied. Lasers based on asymmetric heterostructures with ultrawide (>1 μm) waveguides demonstrate lasing in the fundamental transverse mode with an internal optical loss of as low as 0.34 cm^?1. In laser diodes with a cavity length of more than 3 mm, the thermal resistance is reduced to 2°C/W, and the characteristic temperature T ₀= 10°C is obtained in the range 0–100°C. A record-breaking wallplug efficiency of 74% and an output optical power of 16 W are reached in CW mode. Mean-time-between-failures testing for 1000 h at 65°C with an operation power of 3–4 W results in the power decreasing by 3–7%.     

Properties of wide-mesastripe InGaAsP/InP lasers

Wide-mesastripe InGaAsP/InP heterostructure lasers emitting at 1.3–1.5 µm were grown by metal-organic chemical vapor deposition (MOCVD). Radiation-power-current and spectral characteristics of the lasers have been studied in pulsed and continuous wave (cw) operation in the temperature range of 10–60°C. The temperature of the active region of the diode laser is higher by 30–60°C than that of the copper heatsink upon saturation of the cw output power. The temperature dependence of the differential quantum efficiency strongly affects the cw output power. Output powers of 3 and 2.6 W are achieved in mesastripe lasers in cw operation, and 9 and 6.5 W in pulsed operation, at wavelengths of 1.3 and 1.5 µm, respectively.     

Two-section InGaAsP/InP Fabry-Perot laser with a 12 nm tuning range

Wavelength tuning over a 12 nm range is obtained for a two-section InGaAsP/InP Fabry-Perot laser (λ=1.55 μm). The method used to vary the gain profile of the laser allows one to predict the range of possible wavelength tuning. Pis’ma Zh. Tekh. Fiz. 23, 10–15 (March 26, 1997)     

High-power 1.7–1.8 μm single-mode laser diodes

Separate confinement InGaAsP/InP laser heterostructures were grown by metalorganic-hydride vapor-phase epitaxy. High-power single-mode laser diodes of mesastripe design based on these heterostructures operate in a wavelength interval of 1.7–1.8 μm with a maximum continuous room temperature output power of 150 mW. The single-mode lasing regime is maintained up to an output power level of 100 mW.     

Separately bounded InGaAsP high-power laser heterostructures obtained by VPE of organometallic compounds

InGaAsP/InP laser heterostructures with two stressed quantum wells operating in the wavelength range 1.3–1.55 μm were obtained by VPE of organometallic compounds. An optical emission power of 2.4 W was reached for the laser diodes with 100-μm wide strips operated in the continuous lasing mode at 20°C. A minimum threshold current density was 260 A/cm². A differential quantum efficiency η_d= 40% was obtained with a 1.9-mm-long Fabry-Perot resonator. The internal optical losses of the heterostructures are reduced to 2.6–4.2 cm⁻¹.     

Multiwell laser heterostructures fabricated by liquid-phase epitaxy

A methodology has been developed for growing InGaAsP/InP multiwell laser heterostructures by liquid-phase epitaxy. Depth profiling using a secondary ion mass spectrometer was used to investigate the distribution profiles of the composition of multiwell laser heterostructures. Liquid-phase epitaxy was used to fabricate InGaAsP/InP multiwell laser heterostructures with active regions having emission wavelengths of 1.3 and 1.55 μm and their radiative characteristics were studied. Pis’ma Zh. Tekh. Fiz. 24, 61–67 (November 12, 1998)     

Quantum-Cascade Ring Resonator Laser with 7–8 μm Wavelength and Surface Radiation Output

Semiconductors - We have created a quantum-cascade laser with 7–8 μm wavelength and surface radiation output through a lattice formed by focused ion beam etching of the upper cladding of...     

Heterostructures of Quantum-Cascade Laser for the Spectral Range of 4.6 μm for Obtaining a Continuous-Wave Lasing Mode

Technical Physics Letters - The method of molecular-beam epitaxy was used to fabricate an elastically balanced heterostructure of a quantum-cascade laser for the spectral range of 4.6 μm based...     

A Study of the Spatial-Emission Characteristics of Quantum-Cascade Lasers for the 8-μm Spectral Range

Technical Physics Letters - Near- and far-fields of quantum-cascade lasers emitting in the spectral range near 8 μm have been studied. For all laser samples with a ridge width of 20 and 50...     

High-power broad-band single-mode InGaAsP/InP superluminescent diode

An InGaAsP/InP separate-confinement double heterostructure having a broad gain profile was used to fabricate superluminescent diodes having high optical power (40 mW), a broad radiation spectrum (65 nm at half-width), and low percent modulation (<1%). Using a cw pump current of 150 mA, 1mW of superluminescence radiation was obtained at the exit from a single-mode optical fiber. Pis’ma Zh. Tekh. Fiz. 25, 16–22 (August 12, 1999)