Single-Shot, High-Speed, Thermal-Interface Characterization of Semiconductor Laser Arrays

Through a detailed characterization of thermally induced output power degradation it is possible to use junction heating as a tool to resolve thermal interfaces on mus timescales using a single-shot characterization technique. In this work, the deleterious effect junction heating has on the optical output power of a laser array is characterized and then used to infer the time-dependent junction temperature in response to current pulses of varying widths. The extracted parameters are also used numerically to model the laser as a temperature-dependent heat source for thermal simulations. This treatment allows realistic packaging and emitter-placement studies to be parametrically performed by incorporating the relationship between temperature and output power/efficiency for each emitter. In this respect, once the temperature behavior of a single emitter is quantified, the operating temperature and output power performance can be accurately predicted for any realistic physical arrangement of laser array and packaging. The experimental method presented in this work is also compared to other techniques and numerical simulations using the nonlinear heat source; this demonstrates the utility of this approach and the convenience of using easily measured parameters in thermal simulations.