Linking the 474 THz HeNe/I/sub 2/ standard to the 445 THz single Sr/sup +/ trapped ion standard: heterodyne frequency measurements using an OsO/sub 4/ stabilized 29 THz laser system

摘要

A 29 THz CO/sub 2/ laser system operating on the 10 /spl mu/m R(0) line has been developed, which is frequency-stabilized by third harmonic locking to a saturated absorption resonance of OsO/sub 4/. By difference frequency mixing this radiation and 474 THz radiation referenced to a HeNe/I/sub 2/ laser standard, sufficient 445 THz power is obtained for an absolute heterodyne measurement of the 445 THz radiation probing a /sup 88/Sr/sup +/ single ion reference transition. A new series of measurements give a value of 444779044086 kHz/spl plusmn/12 kHz for the /sup 88/Sr/sup +/, 5s/sup 2/S/sub 1/2/-4d/sup 2/D/sub 5/2/ center frequency.