High power DBR lasers for optimized pumping of chip-scale He:Rb lasers

ABSTRACT: This Phase I SBIR proposal is submitted to address critical component technology for integrated fast light micro-inertial sensors for GPS denied navigation. One promising sensor type is the superluminally enhanced ring laser gyro (SEA-RLG). This proposal addresses development of high-power narrow-linewidth diode laser pump sources for low-power He:Rb alkali vapor lasers at the heart of the SEA-RLG. These are specialized variants of diode-pumped alkali vapor lasers (DPALs) with an emphasis on minimum input pump power and lasing threshold. The key thrust of this work is development of narrow-linewidth 780nm DBR lasers to efficiently pump small He:Rb alkali vapor cells allowing lasing and inhomogeneously broadened gain at the 795nm Rb D1 line. The end goal is to enable chip-scale integration of these He:Rb lasers into compact SEA-RLGs. From previous work, it has been shown that DPAL optical pumping is best accomplished with narrow-linewidth pump sources rather than conventional diode lasers. It has also been shown that the typical minimum pump power required to initiate DPAL lasing is on the order of 300mW to 500mW total. The single element tapered DBR lasers to be developed under this work present ideal candidates for high efficiency pumping of micro-He:Rb DPAL lasers. BENEFIT: The proposed program has benefits to numerous DoD and commercial applications requiring precision inertial sensing, timing, and navigation. Components developed in this work will benefit other researchers and systems integrators working in the fields of atom optics, cold atom physics, alkali atom-based timing, and inertial navigation systems.