C. Lindström

Phase‐locked (GaAl)As laser emitting 1.5 W cw per mirror

A phase‐locked multiple quantum well (GaAl)As injection laser is demonstrated to emit over 1.5 W/mirror (>3 W total) cw output power at ∼8350 A with a maximum power conversion efficiency of 17.4%.

Near-field and far-field patterns of phase-locked semiconductor laser arrays

A gain‐guided phase‐locked semiconductor laser array has been observed to emit a single narrow lobed far‐field radiation pattern up to 70 mW, at which power level it exhibits a distinct change. We show that this effect results from a new phase‐locked mode attaining threshold; the original mode remains phase locked above this power level.

cw room‐temperature operation of GaAlAs single quantum well visible (7300 Å) diode lasers at 100 mW

100‐mW room‐temperature cw laser operation at 7300 A has been achieved in a Ga1−xAlxAs (x∼0.22), ∼300 A thick, single quantum well double heterostructure diode grown by organometallic vapor phase epitaxy. The proton‐delineated stripe contact is 6 μm wide, and the front and rear laser facets are coated for antireflection and high reflection respectively. The cw threshold current is 86 mA for a 250‐μm‐long device, and linear output power versus current characteristics are observed up to 100 mW with an external differential quantum efficiency of 1 W/A (59%). cw output power exceeds 13 mW at 100 °C. Between 25–55 °C, the pulsed threshold current varies exponentially with temperature T as exp(T/T0), where T0∼187 K.

Photopumped low threshold Alx″Ga1−x″As ‐Alx′Ga1−x′As‐AlxGa1−xAs (x″∼0.85, x′∼0.3, x=0) single quantum well lasers

Data are presented showing that it is possible to photopump and operate a quantum well heterostructure laser at equivalent current densities (Jeq) as low as 70 A/cm2. Continuous 300‐K laser operation of a single 60‐A GaAs (x=0) quantum well in the center of a ∼0.12‐μm‐thick x′∼0.30 Alx′Ga1−x′As waveguide (and carrier reservoir), which is confined by x″∼0.85 Alx″Ga1−x″As layers, is demonstrated at Ieq∼0.4 mA (168 W/cm2, Jeq∼70 A/cm2). These quantum well heterostructures are grown by organometallic vapor phase epitaxy.

Dynamic and noise properties of multiple quantum well injection lasers

The fast pulse response and the dc noise spectra of multiple quantum well lasers grown by metalorganic chemical vapor deposition and with different stripe widths are reported. A best rise time of 100 ps corresponding to a modulation bandwidth of ∼3.6 GHz, was obtained. The dc noise spectra showed a damped shot noise resonance at a high frequency (∼3.0 GHz). The improvement in pulse and noise performances of these lasers compared to conventional double heterostructure lasers is explained with the small active volume and the high charge densities present in quantum well lasers.

Visible cw single quantum well (AlGa)As diode lasers

In this letter we report on visible cw single quantum well (AlGa)As diode lasers grown by metalorganic chemical vapor deposition. The operating wavelength is 7210 A. A linear output power up to 10 mW for a threshold current of 75 mA is achieved. The laser consists of a single quantum well double heterostructure with a 9‐μm‐wide proton implanted stripe. Double peaked far‐field patterns, modulation bandwidths to 2.7 GHz, and a flat noise spectra with a reduced shot noise peak at 2 GHz are obtained.