摘要： State of the art diode laser light sources for high power operation with good beam quality are distributed Bragg reflector tapered diode lasers (DBR-TPLs). These devices deliver over 10 W of spectrally narrowband emission within an almost diffraction-limited beam [1]. However, due to the integration of the tapered section into the resonator, these devices are designed that only a forward traveling wave is optimal confined and amplified. This trade-off limits the potential of these devices. One way to overcome this limitation is to move the tapered section outside of the resonator and use as a single pass power amplifier in a monolithic master oscillator power amplifier (MOPA) layout [2]–[4]. However, the benefits on the emissions characteristics, as discussed below, of these devices can diminish if multi-cavity operation occurs. In this work, we present results on recently developed monolithic MOPAs for enhanced suppression of multi-cavity operation. The MOs in these devices are 2 mm long with a 7th order DBR grating at the front- and backside and a 0.75 mm long active section in the middle. An active 0.5 mm long control section (CON) follows the MO section. Both have a ridge waveguide (RW) width of 5 μm. The PA section is 3.5 mm long and defined by the tapered p-side contact with a full angle of 6°. The 3 different layouts are depicted in Fig. 1 a). In the first layout (top) all three section are in a straight line perpendicular to the front facet. The second layout (middle) has a MO section tilted by 4° and a bent CON section and the third layout (bottom) has bent CON section and a PA section tilted by 4°. Fig. 1 a) Sketch of all three monolithic MOPA layouts. b) Optical output power (solid lines) and the peak wavelength (dots) for three different monolithic MOPAs. The straight layout is used as reference to discuss the benefits of a bent control section and either a tilted MO or tilted PA on the emission characteristics of the devices. Furthermore the influence of the control section on the emission characteristics of the devices will be presented. This includes a comparison of the optical output power, the spectra and the beam quality factor of the devices. All devices provide over 6 W of optical output power at 1060 nm within a narrow spectral bandwidth below 17 pm (spectrometer resolution limit). However the overall emission characteristics have clear differences as can be seen in Fig. 1 b). Here the optical output power and the peak wavelength are plotted in dependence of the PA current. The laser with the tilted MO layout shows a small increase in output power compared to the straight layout and a reduction of spectral mode jumps for PA currents below IPA = 8 A. For the laser with the tilted PA layout the small spectral mode jumps due to multi-cavity operation are completely suppressed but the output power is reduced by 0.5 W.