Dynamic nuclear polarization and Knight shift measurements in a breakdown regime of integer quantum Hall effect

Nuclear spins are polarized electrically in a breakdown regime of an odd-integer quantum Hall effect (QHE). Electron excitation to the upper Landau subband with the opposite spin polarity flips nuclear spins through the hyperfine interaction. The polarized nuclear spins reduce the spin-splitting energy and accelerate the QHE breakdown. The Knight shift of the nuclear spins is also measured by tuning electron density during the irradiation of radio-frequency magnetic fields.Comment: 3 pages, 2 figures, EP2DS-1

Far-infrared rays control prostate cancer cells _in vitro_ and _in vivo_

We introduce a new effective method to control hormone refractory prostate cancer cells by using an activated rubber/resin form (RB), far-infrared ray emitter, with or without sodium butyrate (SB). The growth of three human prostate cancer cell lines (Du145, PC-3 and LNCaP) was suppressed _in vitro_ and _in vivo_ by using RB, and the cells were eradicated with RB + 3 mM SB. G1 arrest and apoptotic pathway proteins were induced by RB with intensified expressions of apoptosis - related mRNA on cDNA microarray. RB radiates the infra-red rays of the 4 to 25 [mu]m wavelengths to an object which exert a favorable influence on a cancer control. These results may render us a new therapeutic modality in hormone refractory prostate cancer

Magnetization dependent current rectification in (Ga,Mn)As magnetic tunnel junctions

We have found that the current rectification effect in triple layer (double barrier) (Ga,Mn)As magnetic tunnel junctions strongly depends on the magnetization alignment. The direction as well as the amplitude of the rectification changes with the alignment, which can be switched by bi-directional spin-injection with very small threshold currents. A possible origin of the rectification is energy dependence of the density of states around the Fermi level. Tunneling density of states in (Ga,Mn)As shows characteristic dip around zero-bias indicating formation of correlation gap, the asymmetry of which would be a potential source of the energy dependent density of states