Nobuhiko Miura

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Bright light at night improves the alertness of night workers. Melatonin suppression induced by light at night is, however, reported to be a possible risk factor for breast cancer. Short-wavelength light has a strong impact on melatonin suppression. A red-visor cap can cut the short-wavelength light from the upper visual field selectively with no adverse(More)
We review recent cyclotron resonance studies of semiconductors performed in high magnetic fields. This traditional semiconductor characterization method has been used to study some of the recently-developed materials systems, including ferromagnetic III-V semiconductors and two-dimensional electron gases formed in InSb/InAlSb and GaN/AlGaN heterostructures.(More)
We present a theory for the electronic and optical properties of n-and p-type In 1−x Mn x As in ultra-high magnetic fields. An eight-band effective mass model based on the Pidgeon–Brown model and including the wavevector dependence of the electronic states as well as the s–d and p–d exchange interactions with Mn d-electrons is used to determine the(More)
We report theoretical and experimental ultrahigh magnetic field cyclotron resonance ͑CR͒ studies of paramagnetic p-type InAs and InMnAs. Experimental results are compared with an 8 band Pidgeon–Brown model which includes ͑i͒ the wave vector dependence of the electronic states along the magnetic field, and ͑ii͒ s – d and p – d exchange interactions with Mn(More)
We present a theory for electronic and magneto-optical properties of n-type In 1Ϫx Mn x As magnetic alloy semiconductors in a high magnetic field Bʈzˆ. We use an eight-band Pidgeon-Brown model generalized to include the wave vector (k z) dependence of the electronic states as well as s-d and p-d exchange interactions with localized Mn d electrons.(More)
We have carried out an ultrahigh-field cyclotron resonance study of n-type In 1Ϫx Mn x As films, with Mn composition x ranging from 0% to 12%, grown on GaAs by low-temperature molecular-beam epitaxy. We observe that the electron cyclotron resonance peak shifts to lower field with increasing x. A detailed comparison of experimental results with calculations(More)
We have studied the cyclotron resonance of electrons and holes in various types of InMnAs-based structures at ultrahigh magnetic fields. Our observations, in conjunction with an eight-band effective mass model including the s–d and p–d exchange interactions with Mn d-electrons, unambiguously suggest the existence of s-like and p-like delocalized carriers in(More)
In this paper, Enhanced oxidation of SiC(0001) substrates using La<sub>2</sub>O<sub>3</sub> capped annealing has been presented. Compared to thermal oxidation, lower oxidation temperature can be implemented to form SiO<sub>2</sub> layer, owing to higher oxidation rate by 10 times with La<sub>2</sub>O<sub>3</sub> capped oxidation by catalytic effect of the(More)
Thermal oxidation of SiC(0001) substrates with La<sub>2</sub>O<sub>3</sub> capped annealing has been performed. La<sub>2</sub>O<sub>3</sub> capped oxidation has shown improvements in reduced hysteresis and interface state density (Dit) for MOS capacitors. La-silicate grains, agglomerated at the step bunches of SiC substrates, have been confirmed upon(More)
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