We have built the first quantum oscillator working on two-photon stimulated emission of radiation. It oscillates continuously on a degenerate two-photon transition between the levels 40S and 39S of rubidium atoms. The oscillation is sustained in a Q\ensuremath{\simeq} ${10}^{8}$ niobium superconducting cavity at 68.415 87 GHz. At threshold, this new maser system operates with only a few atoms and a few tens of photons at a time in the cavity.We have built the first quantum oscillator working on two-photon stimulated emission of radiation. It oscillates continuously on a degenerate two-photon transition between the levels 40S and 39S of rubidium atoms. The oscillation is sustained in a Q\ensuremath{\simeq}${10}^{8}$ niobium superconducting cavity at 68.415 87 GHz. At threshold, this new maser system operates with only a few atoms and a few tens of photons at a time in the cavity.

Physical Review LettersOct 26, 1987564 citations

Quantum theory of a two-photon micromaser

L. Davidovich, J. M. Raimond, M. Brune +1 more

We present the quantum theory of a microscopic maser operating on a degenerate two-photon transition between levels of the same parity. We derive both a master equation and a Fokker-Planck equation for this system, and show that quantum effects may have a substantial influence on the behavior of the maser. They modify the oscillation threshold and make external triggering of this maser unnecessary, whereas, according to semiclassical theory, such a triggering is required to start up the maser oscillation. We derive the phase-diffusion properties of the field and show that the diffusion coefficient is complex in this case, its imaginary part being associated with a frequency shift of the field inside the cavity. We show that, in steady state, the photon-number statistics is sub-Poissonian for a wide range of pumping rates.We present the quantum theory of a microscopic maser operating on a degenerate two-photon transition between levels of the same parity. We derive both a master equation and a Fokker-Planck equation for this system, and show that quantum effects may have a substantial influence on the behavior of the maser. They modify the oscillation threshold and make external triggering of this maser unnecessary, whereas, according to semiclassical theory, such a triggering is required to start up the maser oscillation. We derive the phase-diffusion properties of the field and show that the diffusion coefficient is complex in this case, its imaginary part being associated with a frequency shift of the field inside the cavity. We show that, in steady state, the photon-number statistics is sub-Poissonian for a wide range of pumping rates.

Physical Review AOct 1, 1987203 citations

The amplitude fluctuations of optical maser light

R.L. Bailey, J. H. Sanders

Physics LettersJun 1, 196415 citations

From Maser to Mazer

Oliver J. Benson, M. Weidinger, Markus Löffler +1 more

In this paper we report on atomic interferometry in the micromaser. The experimentally observed interferences are due to the non-adiabatic mixing of dressed states of the atoms at the entrance and exit holes of the maser cavity, leading to Ramsey-type two-field interaction. The observations are explained on the basis of the micromaser theory. Statistical properties of the maser field are investigated via a measurement of the statistics of the pump atoms that leave the maser cavity. Theoretical expressions for the time dependence of the Fano-Mandel-parameter QA(t) are compared with the experimental data. We demonstrate, that metastability of the maser field and atomic interference strongly influence the approach to a steady state value of QA(t). Furthermore, a theoretical investigation of a maser pumped with ultra-cold atoms is discussed. The interplay between reflection and transmission events of the atoms leads to a photon emission probability that strongly depends on the quantized center-of-mass motion (z-motion) of the atoms. We demonstrate that this mazer operation can be completely different from the ordinary maser pumped by a beam of thermal atoms.In this paper we report on atomic interferometry in the micromaser. The experimentally observed interferences are due to the non-adiabatic mixing of dressed states of the atoms at the entrance and exit holes of the maser cavity, leading to Ramsey-type two-field interaction. The observations are explained on the basis of the micromaser theory. Statistical properties of the maser field are investigated via a measurement of the statistics of the pump atoms that leave the maser cavity. Theoretical expressions for the time dependence of the Fano-Mandel-parameter QA(t) are compared with the experimental data. We demonstrate, that metastability of the maser field and atomic interference strongly influence the approach to a steady state value of QA(t). Furthermore, a theoretical investigation of a maser pumped with ultra-cold atoms is discussed. The interplay between reflection and transmission events of the atoms leads to a photon emission probability that strongly depends on the quantized center-of-mass motion (z-motion) of the atoms. We demonstrate that this mazer operation can be completely different from the ordinary maser pumped by a beam of thermal atoms.

Fortschritte der PhysikNov 1, 19983 citations

Analytic Calculation of the Atom Counting Statistics for the One-Atom Maser

Berthold‐Georg Englert, Ts. Gantsog, Axel Schenzle +1 more

Springer eBooksJan 1, 19961 citation

{10}^{8}

niobium superconducting cavity at 68.415 87 GHz. At threshold, this new maser system operates with only a few atoms and a few tens of photons at a time in the cavity.