A quantum cascade laser-based gas analyzers with table-top size are developed for the acetone and isotope of carbon dioxide. The precision of 0.1 ppm and 0.3 ‰ in delta notation are achieved respectively.
We have developed a 389-nm frequency-doubled nanosecond-pulsed coherent light source with injection seeding for nuclear polarization of <sup>3</sup>He atoms with 2<sup>3</sup>S→3<sup>3</sup>P and then suggested four kinds of spectroscopic methods with the injection-seeded light source. With this light source, we have conducted saturated absorption spectroscopy of metastable <sup>3</sup>He atoms. As a result, an accurate resonance frequency of 770682 GHz and a dip width of 1.7 GHz of metastable <sup>3</sup>He atoms are obtained. Therefore, the linewidth of our injection-seeded light source can be estimated at 65 MHz or 1.7 GHz. Our light source has potential for the polarization of <sup>3</sup>He due to high-peak power and narrow linewidth of the injection-seeded light source.
We have developed the advanced technology for the frequency stabilization of a nanosecond deep-ultraviolet coherent
light source toward manipulating semiconductor atoms by injection locking with a single-frequency Ti:sapphire laser. In
order to stabilize injection seeding, we utilized the small change of the build-up time of the slave-laser pulse. The injection-locked laser can acquire significant performances of both narrow linewidth and high peak power. As a result, the fluctuation of the wavelength decreases from 2.1 GHz to 10 MHz due to the injection seeding. The laser performance indicates various potentials useful for manipulating semiconductor atoms.
We investigate optical properties of semiconductor atoms by absorption and
emission spectroscopies. Each of <sup>3</sup>P<sub>J'</sub> - <sup>3</sup>P°<sub>J</sub> transitions except for J'=0 (the total angular
momentum of the ground state) is confirmed in broad emission spectra in a hollow-cathode
discharge in which negative electrodes incorporate semiconductor atoms that are evaporated
in the discharge. For finer spectroscopies, the <sup>3</sup>P<sub>1</sub> - <sup>3</sup>P°<sub>0</sub> cyclic transition for laser cooling of
silicon atoms at 252 nm is investigated in absorption spectra with a single-frequency tunable
deep-UV coherent light source, which has a high potential for controlling their nuclear spins.
There have been significant progresses in atom optics utilizing laser cooling techniques in recent years. Among them, we have been interested in an atomic mirror for silicon which can reflect silicon atoms. The atomic mirror consists of two layers on a sapphire substrate, and then atoms are reflected by the dipole forces from evanescent waves caused by the light reflected internally and totally at the interface of different refractive indices. In this study, we have constructed some structures of the atomic mirror.
We tried atomic layer deposition techniques for preparation of both Al<sub>2</sub>O<sub>3</sub> and TiO<sub>2</sub> thin films, whose surface and interface roughnesses are well suppressed. In order to achieve the predicted enhancement of the evanescent waves, atomic layer deposition of the layer with the higher refractive index is especially important. It has found that absorption can be suppressed considerably by adding Al(CH<sub>3</sub>)<sub>3</sub> precursor gas to the alternate introducing cycle of TiCl<sub>4</sub> and H<sub>2</sub>O<sub>2</sub> precursor gases. We use this effect which can improve homogeneity and flatness of layers significantly, to design an atomic mirror using atomic layer deposition.
A frequency-tripled nanosecond pulsed Ti:sapphire laser injection-seeded by a cw single-frequency
Ti:sapphire laser has been developed. The single-frequency stability of this light source is demonstrated
successfully by matching between the optical frequency of the seed laser and the cavity frequency of the
slave laser with build-up time electronics. It is also discussed with fluctuations of the wavelength of the
Ti:sapphire laser and the optogalvanic signal of silicon atoms. This unique light source opens the door to
silicon atom optics, which is capable of manipulating atoms isotopically for novel material processing.