Electron Diffraction Study of Films of Body-Centered Cubic Metals Condensed at Low Temperature

Metals with the bcc structure (Li, Na, K, Rb, Cs and Ba) have been condensed onto substrates kept at the liquid helium or nitrogen temperature by vacuum evaporation, and their structures have been studied by transmission electron diffraction. It has been found that none of these films are in an amorphous state, and that the films of alkali metals (Li, Na, K, Rb and Cs) contain a small quantity of crystallites of the hop structure besides those of the bcc structure

Time-reversed two-photon interferometry for phase super-resolution

We observed two-photon phase super-resolution in an unbalanced Michelson interferometer with classical Gaussian laser pulses. Our work is a time-reversed version of a two-photon interference experiment using an unbalanced Michelson interferometer. A measured interferogram exhibits two-photon phase super-resolution with a high visibility of 97.9% \pm 0.4%. Its coherence length is about 22 times longer than that of the input laser pulses. It is a classical analogue to the large difference between the one- and two-photon coherence lengths of entangled photon pairs.Comment: 6 pages, 4 figure

Observation of nonlinear variations in three-vertex geometric phase in two-photon polarization qutrit

We experimentally observed nonlinear variations in the three-vertex geometric phase in a two- photon polarization qutrit. The three-vertex geometric phase is defined by three quantum states, which generally forms a three-state (qutrit) system. By changing one of the three constituent states, we observed two rapid increases in the three-vertex geometric phase. The observed variations are inherent in a three-state system and cannot be observed in a two-state system. We used a time-reversed two-photon interferometer to measure the geometric phase with much more intense signals than those of a typical two-photon interferometer.Comment: 6 pages, 5 figure

Measurements of stratospheric ozone by rocket ozonesondes in Japan

A small optical ozone instrument has been developed for a rocket-borne dropsonde to measure the altitude profile of stratospheric ozone. It consists of a four-color filter photometer that measures the attenuation of sunlight as a function of altitude at four wavelengths in the middle ultraviolet. The ozone dropsonde is launched aboard a meteorological rocket MT-135, providing the altitude profiles of ozone as well as atmospheric temperature and wind. The rocket launchings have been carried out five times since August 1990 at Uchinoura (31 deg N, 131 deg E), Japan to measure ozone concentration from 52 to 20 km altitudes during the slow fall of the dropsonde. The ozone profiles measured in summer (August 27, 1990; Sep. 11 and 12, 1991) were very stable above an altitude of 28km. where as those measured in winter (Feb. 9, and 11, 1991) showed considerable day-to-day variations at the stratospheric altitudes. Ozone, temperature and wind profiles measured simultaneously by both rocket and balloon ozonsondes are compared with CIRA 1986 model atmosphere

Electron Diffraction Study on the Structure of Amorphous Films Prepared by Low Temperature Condensation : I. Apparatus and Preliminary Results

An electron diffraction camera equipped with a sector has been constructed which enables one to observe diffracted intensities at sufficiently large scattering angles in order to improve the radial distribution analysis of electron diffraction patterns. Values of the structure-sensitive intensity I_m(s) have been obtained in the range from s=1.2 to 22.0 A^ for an amorphous tellurium film condensed onto substrate at the liquid helium temperature by use of a sector of s^2-type. The radial distribution function of the film is also calculated from the obtained I_m(s)