FREQUENCY STABILIZATION OF A HENE LASER AT 543.5-NM WAVELENGTH USING FREQUENCY-MODULATION SPECTROSCOPY

Two internal mirror HeNe lasers emitting at 543.5 nm wavelength were frequency stabilized to hyperfine components of the iodine R(12)26-0 and R(106)28-0 transitions utilizing frequency-modulation spectroscopy. Beat frequency measurements yielded difference frequencies which differ in a range of +1.8 kHz to -0.8 kHz. Realizing nearly shot noise limited detection, the minimum two probe standard deviation of 2.7 x 10(-13) was reached at a sampling time of 10000 s using an iodine pressure of 1.44 Pa. From the measured hyperfine line splitting hyperfine structure coupling contants have been calculated. The wavelength of the reference HFS-component a9 has been measured.