We report on work directed toward the systematic evaluation of an optical frequency standard based on the S1/2–D5/2 transition of a single, laser-cooled, trapped 199Hg+ ion, whose resonance frequency is 1.06 × 1015 Hz. For the purpose of the evaluation, two 199Hg+ standards have been constructed. In the cooling-laser system built for the second standard, an injection-locking scheme has been app...

The 2.1-/im 5I7-518 laser transition in Ho3+ is attractive because of its long upper laser level lifetime, of the order of 5 msec, and its eye-safe wavelength. However, this laser typically is cooled to liquid-N2 temperatures to achieve continuous-wave (cw) or high-repetition-rate operation because its lower laser level is in the ground-state manifold, a few hundred inverse centimeters above th...

We report a two-color magneto-optical trap (MOT) for ytterbium atoms operating at a low magnetic field gradient down to 2 G/cm where a conventional MOT using the singlet transition (6s 1S0 → 6s6p 1P1) is unable to trap atoms. By simultaneously applying laser light on both the broad-linewidth singlet transition and the narrow-linewidth triplet transition (6s 1S0 → 6s6p 3P1), we load and trap 4.0...

When the carrier density is increased in a semiconductor, according to the predictions of Sir Nevil Mott, a transition should occur from an insulating state consisting of a gas of excitons to a conductive electron-hole plasma. This crossover, usually referred to as the Mott transition, is driven by the mutual effects of phase-space filling and Coulomb screening because of the presence of other ...

H-like and He-like resonantly photo-pumped laser schemes were proposed for producing X-ray lasers nearly four decades ago. However, demonstrating these schemes in the laboratory has proven to be elusive. One major challenge has been the difficulty of finding an adequate resonance between a strong pump line and a line in the laser plasma that drives the laser transition. After finding a good res...

We investigate the spectrum of resonance uorescence of laser driven three-level systems in the V or connguration where one transition is metastable. If the laser driving the weak transition has a suuciently small Rabi frequency we nd an extremely narrow structure in the resonance uorescence spectrum of the strong transition. Analytical expressions approximating the spectrum are given and the pr...

We have built a high-accuracy wavelength meter for tunable lasers using a scanning Michelson interferometer and a reference laser of known wavelength. The reference laser is a frequency stabilized diode laser locked to an atomic transition in Rb. The wavemeter has a statistical error per measurement of 5 parts in 10 which can be reduced considerably by averaging. Using a second stabilized diode...

Terahertz (THz) pulses with energies up to 100 μJ and corresponding electric fields up to 1 MV/cm were generated by coherent transition radiation from 500 MeV electron bunches at the free-electron laser Freie-Elektronen-Laser in Hamburg (FLASH). The pulses were characterized in the time domain by electro-optical sampling by a synchronized femtosecond laser with jitter of less than 100 fs. High ...

A compact mid-infrared channel waveguide laser is demonstrated in Cr:ZnS with a view to power scaling chromium laser technology utilizing the thermo-mechanical advantages of Cr:ZnS over alternative transition metal doped II-VI semiconductor laser materials. The laser provided a maximum power of 101 mW of CW output at 2333 nm limited only by the available pump power. A maximum slope efficiency o...