Skyrmions and their interactions using the Atiyah-Manton construction

The Atiyah-Manton (AM) construction based on instantons is used to construct skyrmions. For baryon number one, an analytic form for the skyrmion is obtained that compares well with the exact solution. For baryon number two, we study skyrmion interactions and distortion as a function of relative distance and orientation. From this we project out a nucleon-nucleon interaction. We find the principal features of the nuclear force but still no intermediate-range attraction. We compare the AM construction with the product ansatz.     

Microscopic approach to the antiproton-nucleus optical potential

By using the self-energy of an antiproton evaluated in nuclear matter, the antiproton effective interaction with a bound nucleon is derived and is found to have a drastic density dependence. The p?-nucleus optical potential constructed by folding the effective interaction well reproduces experimental data on the p?-nucleus absorption cross section as well as on the complex level shift of p?-atoms. In addition, it is pointed out that the strong spin-orbit interaction spreads each doublet and considerably affects the lower complex level shift.     

Resonance Raman scattering of excitonic polaritons by LO and acoustic phonons in ZnTe

We have observed dispersive two-phonon Raman scattering of polaritons by LO and acoustic phonons near the lowest exciton state of ZnTe. From the Stokes shifts of these Raman lines, it has been found that the scattering process switches from an acoustic phonon followed by one LO phonon to the reversed one: a LO phonon followed by an acoustic one.     

Stimulated emission effects in excitonic molecule luminescence of CuCl under resonant two-photon excitation

Luminescence spectra of excitonic molecules in CuCl resonantly created by nano-second dye laser excitation are measured at 4.2 K changing the lenghts of the excited region. The spectra are dominated by stimulated emission. The gain coefficient for the M_T line is saturated more easily than that for M_L, though the former is larger under unsaturated conditions. These gain characteristics explain well various stimulated emission effects observed.     

Δk = ±3 “forbidden” infrared transitions in the ν2-band of NH3

Two Δk = ±3 “forbidden” vibration-rotation transitions in the ν₂-band of NH₃ have been measured by using infrared-microwave two-photon spectroscopy and laser Stark spectroscopy. Combining these results with Rao's recent measurement of the band, we have obtained the C₀ rotational constant of 6.2280 ± 0.0008 cm^?1.     

Studies of relaxation times of secondary radiations in ZnTe by circular polarization correlation

Population and spin relaxation rates concerned with exciton luminescence and multiple LO-phonon emission lines are studied in ZnTe at 77 K by means of optical circular polarization correlation between the exciting and emitted lights. The decay times of the LO lines are determined to be much less than 10^-11sec, which are definitely shorter than the obtained exciton lifetime of 10^-10-10^-9sec. It is concluded that the LO lines are not due to hot luminescence but due to resonance Raman scattering.