Spectroscopy in vapour cells

The method typically used in vapour cell atomic clocks (Rubidium standards) is the laser-microwave double-resonance spectroscopy. Our research is devoted to the study of alternative light-atom interaction schemes that could replace the laser-microwave double-resonance principle in some clock applications. In particular, we study experimentally studies the Coherent Population Trapping (CPT) effect occurring in Rubidium isotopes for different excitation schemes. Laser spectroscopy techniques are used to evaluate the metrological properties of the CPT effect. The dependence of the CPT parameters (amplitude, linewidth and resonant frequency) as a function of the most significant experimental parameters (for instance the external magnetic field and the alkali atom density) is studied for different types of cells (cm and mm cells, coated cells or cells filled with buffer gas).

The goal of this activity is to find the experimental conditions in which CPT signals may be used in future compact high performance atomic clocks and in future miniature clocks.

Relevant publications:

  1. G. Kazakov , B. Matisov, I. Mazets, G. Mileti, and J. Delporte, Pseudoresonance mechanism of all-optical frequency-standard operation, Physical Review A, Vol. 72, 063408, (December 2005).
  2. G. Kazakov , B. Matisov, I. Mazets, and G. Mileti, Optimised scheme of a Rubidium all-optical frequency standard, Technical Physics Letters, Vol. 31, No. 12, pp. 1009-1010, (December 2005).


  1. E. Breschi, G. Kazakov, R. Lammegger, B. Matisov, G. Mileti, L. Windholz, Study of the laser linewidth influence on lin||lin Coherent Population Trapping, TimeNav' 2007, EFTF European Frequency and Time Forum Geneva - Switzerland, (May 29 - June 2, 2007) Proceeding submitted.
  2. G. Kazakov, E. Breschi, B. Matisov, I. Mazets , C. Schori, C. Affolderbach, J. Delporte and G. Mileti, Evaluation of the CPT pseudo-resonance scheme for all optical 87Rb frequency standard, 20th European Frequency and Time Forum (EFTF) pp. 246-252, Braunschweig - Germany, (2006).
  3. G. Kazakov , I. Mazets, Yu. Rozhdestvensky, G. Mileti, J. Delporte, and B. Matisov, High-Contrast Dark Resonance on the D2 - Line of 87Rb in a Vapor Cell with Different Directions of the Pump - Probe Waves, ESA Special Publication "First Workshop on Optical Clocks", pp. 85-90, (2006).


  1. E. Breschi, G. Kazakov, R. Lammegger, B. Matisov, G. Mileti, L. Windholz, lin lin Coherent Population Trapping and its application in vapor-cell-atomic-clocks, Conference on Laser and Electro-Optics (CLEO)- IQEC 2007, Munich - Germany, (June 18 - 22, 2007).
  2. E. Breschi, C. Affolderbach, G. Mileti, G. Kazakov, B. Matisov, I. Mazets, Investigations on the CPT effect in p configuration: the 'pseudo-resonance' mechanism, 38th Conference of the European Group on Atomic Spectroscopy, Ischia - Italy, (June, 2006).
  3. E. Breschi, C. Affolderbach, G. Mileti, Experimental investigation of Coherent Population Trapping in Rubidium vapor for applications in high performances and chip scale atomic clock, Annual meeting of the Swiss Physical Society (SPS), EPFL, Lausanne - Switzerland, (February 2006).