58 -- MODE LOCKED TI: SAPPHIRE LASER

The U.S. Department of Commerce, National Institute of Standards & Technology (NIST) proposes to negotiate on a sole source basis contract under the authority of 41 U.S.C. 253(c)(1) with Coherent Laser Group to purchase a mode locked ti:sapphire laser. The current laser system is composed of 3 parts, a pump laser, a mode locked ti:sapphire laser, and an optical parametric oscillator (OPO). A single vendor of all three parts is required to ensure compatibility. To meet our needs, the output of the ti:sapphire laser must meet the following specifications:Autocorrelation: Greater than 200 fs, but less than 100 fs Average power: Less than 650 mW (using 5 watt solid state 532 nm pump source) Tuning range: 700-980nm with a single optics set RMS noise: Greater than 0.1% (10Hz-20MHz) Polarization: Horizontal Repetition Rate: 76 MHz 1) System must be completely compatible and characterized with the Coherent Verdi pump laser and Mira-OPO synchronously-pumped optical parametric oscillator. 2) The laser must be passively mode locked and use a variable saturable absorber or slit for preferential control between CW and mode locked operation. This configuration provides a means for controlling loss differential as well as gain differential which is necessary for reliable operation and control of the spectral purity of the mode locked output. The system must not use active electronic modulation such as AO modulators. Our measurements would be completely compromised if CW breakthrough components were present in the mode locked pulse spectrum, and would make many of our experiments impossible. It is therefore imperative that the system must include a mechanism for directly controlling differential loss in the laser cavity. Completely eliminating CW breakthrough can only be accomplished by controlling not only differential gain but also differential loss in the system. Controlling loss differential eliminates the need for us to make adjustments to pump power, mode quality, and cavity alignment that cannot completely remove CW breakthrough as required over the duration of the experiments. 3) The laser must use a birefringent filter wavelength-tuning element. Moving slit tuning elements are unacceptable because of their wavelength drift. 4) The system must have a starter mechanism that reproducibly initiates mode-locked operation and shuts off automatically one the mode-locking has started. 5) Variable group velocity dispersion compensation must be provided with a simple 2-prism configuration within the laser cavity. Four-prism configurations are unacceptable because of possible beam motion. 6) To simplify optical alignment, the laser must have a horizontal, two-dimensional optical path. 7) The system must have internal pump laser steering optics mounted to the laser base plate for maximum stability and control of the pump beam position into the ti:sapphire crystal. These mounts must provide independent translational and rotational positioning of the pump beam. 8) The laser must be able to be pumped from the side so that no turning mirror is required outside the laser to direct the pump beam into the cavity. This configuration allows the laser to be positioned as the corner of the optical table for convenient integration with our experiments. 9) The system must include a complete integrated diagnostics system with the following: a) an integral scanning interferometer to detect any CW spectral features which are displayed on the control unit to warn the user of this unwanted component in the mode locked pulse train, b) an integral power meter/fluorescence detector that has a five decade auto ranging circuit is used to align the laser when changing optics or switching modes of operation, c) an integral humidity detector to monitor purging effectiveness when tuning in wavelength ranges that are susceptible to absorption by water vapor. This procurement is being conducted per FAR Part 13, Simplified Acquisition Procedures (NTE $100K). This synopsis is issued for information only. No competitive solicitation is planned. Based on our market research, Coherent Laser Group is the only vendor who can meet the requirements of this procurement. Information submitted in response to this notice will be used solely to determine whether or not use of competitive procedures to fulfill this requirement would be in the Government's best interest and must address qualifications pertinent to this requirement. Terms and Conditions can be found on http://www.arnet.gov/far/ and agency level protest procedures can be found on web site http://oamweb.osec.doc.gov/conops/reflib/alp1296.htm. Any questions regarding this notice must be submitted in writing to Ms. Rima (e-mail preferred). Anticipated award date is January 3, 2005.