2014 Dichroism and birefringence are studied for the case of a strong saturating laser and a linearly polarized weak probe laser interacting with a dilute gas. For linearly or circularly polarized saturating laser fields the optical analog of the Kerr or Faraday effect are obtained respectively. Two photon, Doppler-free polarization effects are studied for two and three level systems (J = 0 ~ J...

At PTB we have developed an optical frequency standard based on laser cooled calcium atoms. A laser is frequencystabilized to the intercombination transition at a wavelength of 657 nm by means of time-domain atom interferences. The dependence of its frequency on various parameters was investigated by using different excitation schemes corresponding to phase sensitive and frequency sensitive ato...

We consider microwave hyperfine transitions in the ground state of cesium and rubidium atoms which are presently used as the primary and the secondary frequency standards. The atoms are confined in an optical lattice generated by a circularly polarized laser field. We demonstrate that applying an external magnetic field with appropriately chosen direction may cancel dynamic Stark frequency shif...

Electromagnetically induced transparency is predicted for x rays in laser-dressed neon gas. The x-ray photoabsorption cross section and polarizability near the Ne K edge are calculated using an ab initio theory suitable for optical strong-field problems. The laser wavelength is tuned close to the transition between 1s(-1)3s and 1s(-1)3p approximately 800 nm). The minimum laser intensity require...

We demonstrate a robust method of stabilizing a diode laser frequency to an atomic transition. This technique employs the Zeeman shift to generate an antisymmetric signal about a Doppler-broadened atomic resonance, and therefore offers a large recapture range as well as high stability. The frequency of a 780-nm diode laser, stabilized to such a signal in Rb, drifted less than 0.5 MHz peak-peak ...

We demonstrate optical tuning of the scattering length in a Bose-Einstein condensate as predicted by Fedichev et al. [Phys. Rev. Lett. 77, 2913 (1996)]. In our experiment, atoms in a 87Rb condensate are exposed to laser light which is tuned close to the transition frequency to an excited molecular state. By controlling the power and detuning of the laser beam we can change the atomic scattering...

Time-resolved x-ray diffraction with picosecond temporal resolution is used to observe scattering from impulsively generated coherent acoustic phonons in laser-excited InSb crystals. The observed frequencies and damping rates are in agreement with a model based on dynamical diffraction theory coupled to analytic solutions for the laser-induced strain profile. The results are consistent with a 1...

A high-power diode-cladding-pumped Ho³⁺-doped fluoride glass fiber laser operating in cascade mode is demonstrated. The ⁵I₆→⁵I₇ and ⁵I₇→⁵I₈ laser transitions produced 0.77 W at a measured slope efficiency of 12.4% and 0.24 W at a measured slope efficiency of 5.2%, respectively. Using a long fiber length, which forced a large threshold for the ⁵I₇→⁵I₈ transition, a wavelength of 3.002 μm was mea...

We report the production of optically spaced attosecond electron microbunches produced by the inverse free-electron-laser (IFEL) process. The IFEL is driven by a Ti:sapphire laser synchronized with the electron beam. The IFEL is followed by a magnetic chicane that converts the energy modulation into the longitudinal microbunch structure. The microbunch train is characterized by observing cohere...

We demonstrate the generation of two high-power laser beams whose frequencies are separated by the ground state hyperfine transition frequency in (87)Rb. The system uses a single master diode laser appropriately shifted by high frequency acousto-optic modulators and amplified by semiconductor tapered amplifiers. This produces two 1 W laser beams with a frequency spacing of 6.834 GHz and a relat...