This is a Sources Sought notice for a high-speed swept laser, which is a mission-critical component for NIST's multi-year, multi-million dollar Standard Photonic Thermometer project. The laser must meet detailed technical specifications, including a center wavelength of 1550 nm, a tunable sweep range from 15 nm to 70 nm, a sweep frequency of 150 Hz or more, and a coherence length over 100 m. The performance location is not specified. Interested parties must respond by email to the provided points of contact, and questions must be submitted by 5:00 p.m. Eastern Time on April 13, 2026. The response should include company details, capabilities, past performance, and feedback on the requirements.