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The United States Naval Observatory (USNO) is researching new clock technology for future integration into the USNO clock ensemble and master clock. Current efforts are focused on investigating alkali... The United States Naval Observatory (USNO) is researching new clock technology for future integration into the USNO clock ensemble and master clock. Current efforts are focused on investigating alkaline-earth optical clocks, one of which is a strontium lattice clock. Integral to the development of this type of optical clock is the ability to laser cool and trap the strontium emitted from an atom source. The primary electronic transition associated with laser cooling of strontium is resonant with laser light of wavelength 460.8624 nm. This transition has a short excited state lifetime, lending itself as an ideal transition for laser cooling. For the USNO’s application, this laser wavelength is the workhorse for multiple stages of laser cooling (transverse cooling, Zeeman slowing, 2D and 3D magneto-optical traps, etc.). Each of these stages requires moderate laser powers. We intend to accomplish all of our laser cooling stages with one laser system. Therefore, it is crucial that the single laser source have sufficient power for all the stages of laser cooling and trapping of strontium. For consistent and reliable laser cooling, it is necessary to stabilize the frequency of the laser system to an external reference. In an effort to avoid delegation of laser power in the primary output beam to laser stabilization, we require a second \probe output beam coupled to the spectral properties of the main output beam. In the absence of a secondary output, the total primary output power must be elevated to account for the need to frequency stabilize the laser. Additionally, there must be electronic inputs on the laser system that allow for external feedback to control the frequency of the laser. The USNO’s seek to procure a laser system for our work on strontium, a 460.8624 nm laser system to laser cool and trap strontium atoms. The necessary laser must meet the following specifications: 1. The laser must have a mode-hop free tuning range of at least 10 GHz, and it must satisfy the wavelength specification centered at a wavelength of 460.862 nm. 2. The laser must have access to alignment controls for course tuning of the laser wavelength on the order of 1 nm. 3. The laser must emit light in a single transverse and longitudinal mode, with a line width of 500 kHz or less. This line width must be achievable in a standard laboratory environment, without user provided vibration isolation. 4. The system must include an optical isolator(s) at critical stages in the laser system, providing 25 dB isolation. 5. The laser must have the following output characteristics: i. Primary output at least 800 mW of power into a collimated free-space beam with linear polarization. ii. Secondary output \probe into a collimated free-space beam with linear polarization. Absent a secondary output, the total primary output must be at least 900 mW. 6. The laser must have electronic inputs to allow external feedback to the frequency of the laser for stabilization/modulation. 7. The laser must be turnkey, including controllers for independent wavelength control, thermal control, and current control of the laser, and requiring no user alignment. Please see attached solicitation for further details.