Efficient, High Power, Wide-Aperture Single Emitter Diode Lasers Emitting at 915 nm

• Published in: IEEE photonics technology letters Vol. 36; no. 16; pp. 977 - 980
• Main Authors: Arslan, Seval, King, Ben, Della Casa, Pietro, Martin, Dominik, Thies, Andreas, Knigge, Andrea, Crump, Paul
• Format: Journal Article
• Language: English
• Published: New York IEEE 15.08.2024; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Continuous radiation; Couplings; Diode lasers; Emitters; Energy conversion efficiency; fiber coupling; Heat sinks; High-power; Optical fiber devices; Pulse duration; Semiconductor lasers; Stimulated emission; Structural rings; Three-dimensional printing; Threshold current
• ISSN: 1041-1135; 1941-0174
• DOI: 10.1109/LPT.2024.3419552

We present single emitter laser diodes with high optical output power (<inline-formula> <tex-math notation="LaTeX">\boldsymbol {P} {_{\text {out}}} </tex-math></inline-formula>), conversion efficiency (<inline-formula> <tex-math notation="LaTeX">\boldsymbol {\eta } {_{\text {E}}} </tex-math></inline-formula>), and lateral beam quality in quasi-continuous-wave (QCW) and continuous-wave (CW) operations enabled by using very wide stripe width (ranging from 400 to 1500<inline-formula> <tex-math notation="LaTeX">\mu </tex-math></inline-formula>m) and laterally structured p-side contact to prevent higher order and unwanted ring modes. We show that the maximum QCW <inline-formula> <tex-math notation="LaTeX">\boldsymbol {P} {_{\text {out}}} </tex-math></inline-formula> increases for wider stripe and <inline-formula> <tex-math notation="LaTeX">\boldsymbol {P} {_{\text {out}}} </tex-math></inline-formula> of <inline-formula> <tex-math notation="LaTeX">\boldsymbol {\sim }~290 </tex-math></inline-formula>W (limited by facet failure) is obtained at <inline-formula> <tex-math notation="LaTeX">\boldsymbol {\eta } {_{\text {E}}} =60 </tex-math></inline-formula>% for 1500<inline-formula> <tex-math notation="LaTeX">\mu </tex-math></inline-formula>m stripes using 500<inline-formula> <tex-math notation="LaTeX">\mu </tex-math></inline-formula>s pulse width and 10Hz repetition-rate at a heatsink temperature of <inline-formula> <tex-math notation="LaTeX">\boldsymbol {T} {_{\text {HS}}} =25 </tex-math></inline-formula> °C. In contrast, the maximum CW <inline-formula> <tex-math notation="LaTeX">\boldsymbol {P} {_{\text {out}}} </tex-math></inline-formula> of 71W (limited by the available cooling of the test set-up) at <inline-formula> <tex-math notation="LaTeX">\boldsymbol {\eta } {_{\text {E}}} =59 </tex-math></inline-formula>% is obtained for 1000<inline-formula> <tex-math notation="LaTeX">\mu </tex-math></inline-formula>m stripes, with lateral-beam-parameter-product (BPPLat.) < 75mm<inline-formula> <tex-math notation="LaTeX">\boldsymbol {\cdot } </tex-math></inline-formula>mrad, which is suitable for coupling into 1mm core 0.15NA fiber.