Some characteristics of an Rb87 laser

E. V. Kulagin, A. I. Pikhtelev, Yu. P. Tuturkin +2 more

Richard S. Quimby, Richard C. Powell

Han Seb Moon, Lim Lee, Kyoung-Dae Kim +1 more

We present two techniques to lock a laser frequency on an atomic transition line by using an electromagnetically induced transparency (EIT) signals, which give optical and electric feedback. We employed these methods to the D2 line of Rb87 atoms. Spectral characteristics of subnatural linewidth EIT allow us to improve frequency stability. By optical feedback of EIT signals, we were able to obtain locking bandwidths of 12 MHz, while frequency stability was 5×10−13 at best after 100 s of integration using a frequency modulation technique.

Filippo Levi, Godone, Aldo, Salvatore Micalizio +1 more

The possibility of using a three-level-A-scheme for the excitation of the clock hyperfine transition in Rb87 is analyzed. The physics involved opens up two distinct avenues useful for the implementation of an atomic frequency standard, avenues based on two distinct phenomena: the electro-magnetically induced transparency (EIT or Dark Line) and the coherent microwave emission (Maser without population inversion). In spite of the close connection between the two phenomena, which are generated by the coherence created in the ground state by means of two coherent laser radiation fields (Coherent Population Trapping), the characteristics of an atomic frequency standard based on either of these phenomena may be quite different. The paper discusses the possibility of implementing on the basis of these two phenomena, new Rb87 atomic frequency standards having an excellent frequency stability, and makes explicit their differences.

Fritz Haake, M. I. Kolohov, Claude Fabre +2 more

Kōichi Shimoda