Spectroscopy of $^1$S$_0 \leftrightarrow ^3$P$_0$ transition in In$^+$

William L. Trimble, Warren Nagourney

Hsuan‐Hao Fan, E. Krotscheck, J. W. Clark

Jinpeng Yuan, Shichao Dong, Lirong Wang +2 more

Abstract We present a laser frequency locking scheme for the high excited transition of rubidium, which cannot be directly referenced by atomic absorption spectroscopy. Double resonance optical pumping spectroscopy and two-photon transition spectroscopy of a 5 S → 5 P → 5 D transition are obtained in a room temperature vapor cell and employed as the reference sources. An Allan deviation of 1.71 × 10 −12 at an averaging time of 2048 s with a residual frequency fluctuation of ±0.2 MHz over 7000 s is obtained by two-photon transition spectroscopy. The case of double resonance optical pumping spectroscopy presents an Allan deviation of 4.86 × 10 −12 at an averaging time of 2048 s with a residual frequency fluctuation of ±0.4 MHz over 7000 s. One distinct advantage of two-photon transition spectroscopy method is demonstrated by the analysis of the fast Fourier transform of error signal. A narrower full width at half-maximum of two-photon transition spectroscopy and a higher zero crossing slope by using a frequency modulation method lead to a better frequency stabilization. This work provides a technical basis for the laser frequency stabilization based on atomic and molecular transition spectroscopy, and it also supplies a new frequency standard for optical telecommunication applications.

Xiaohu Fu, Kangkang Liu Kangkang Liu, Ru-Chen Zhao +4 more

We experimentally observe polarization spectroscopy (PS) of the S01-P31 transition of mercury atom gases at 253.7 nm. The PS signal can be observed in all six richly abundant isotopes and the PS signal of six transitions for laser cooling are all clear and of a dispersive line shape. The optimized pump power and probe power are found for the PS of Hg202. We find the linearly polarized component in the pump beam will distort the original PS signal due to the use of linear PS. Consequently, the purity of the pump beam is crucial to laser frequency stabilization by PS.

Carl Faust, Joshua Jones, Seth Ashman +6 more

Shigeru NAKAYAMA

The relative intensities of the Doppler-free signals in the transition from polarized and dispersive signals to absorptive signals of the Na D1 line are calculated theoretically from the approximation of a single cycle of opticalpumping in a four-level system. The transition from polarized signals to saturated signals is made by varying the angle of an analyzer. Since the signal in polarization spectroscopy is mixed with the signal in saturation spectroscopy during the transition, spurious signals due to saturation and polarization effects should be taken into account in the signal analysis of polarization and saturation spectroscopies, respectively. Both theories, of polarization spectroscopy and saturation spectroscopy are unified and applied to the Doppler-free signals of the Na D1 line. The results obtained from the four-level optical pumping theory which mixes polarization spectroscopy with saturation spectroscopy are in good agreement with experimental reports.