Development of an ultranarrow diode laser for interrogating the 674-nm2S 1/2 -2D 5/2 clock transition in Sr+
G. P. Barwood, K. Gao, Patrick Robert Gill +2 more
An optical frequency standard, based on the 674 nm 2S1/2-2D5/2 'clock' transition in a laser cooled trapped strontium ion is currently being evaluated at the UK National Physical Laboratory. The probe laser is a narrowed AlGaInP diode laser locked to a highly-stable and ultra-low- expansion high-finesse cavity. Laser linewidths of less than 200 Hz have been observed, measured by scanning over a single Zeeman component at 674 nm. The development of this laser is described, together with factors currently limiting the observed linewidth. Three 88Sr+ traps are now in operation, and the probe laser source can be simultaneously locked to the center of the 2S1/2 - 2D5/2 Zeeman multiplet in any two of the three traps, allowing a comparison between them. Recent results on this comparison are presented.
Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•May 3, 2001•7 citations