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81.
First-principles calculations of the band offsets between Cu(2)ZnSnS(4) (CZTS) and XS (X = Cd, Zn) are performed. While the interface dipole contribution for the band offsets is calculated using the Perdew-Burke-Ernzerhof functional, the Heyd-Scuseria-Ernzerhof hybrid functional is employed to introduce the quasiparticle corrections to the band offsets. The calculated conduction band offset between CZTS and CdS is 0.2 eV, validating CdS for the buffer layer of the CZTS solar cell. The small conduction band offset stems from the band gap narrowing of CdS under the interface strain caused by the lattice misfit with CZTS. A large valence band offset over 0.9 eV between CZTS and ZnS indicates that precipitated ZnS is regarded as an inactive insulator phase in CZTS absorbers. 相似文献
82.
We newly synthesized various sized gold nanoparticles covered with photochromic polymers consisting of diarylethenes with various structures to investigate an effect of the gold nanoparticles on the photocycloreversion reaction of the diarylethene chromophores upon irradiation with visible light. The gold nanoparticles covered with the photochromic polymers exhibited reversible changes in localized surface plasmon resonance (LSPR) absorption along with the photochromic reaction depending on the diameter of the particle, the distance between the gold surface and the chromophore, and the structure of the diarylethene chromophore. The rate of the photocycloreversion reaction of the chromophores around the particle was enhanced by the gold nanoparticles and the degree of the enhancement was affected by the diameter of the particle and the distance from the gold surface, while a structural difference in the diarylethene chromophore had no effect on the degree of the enhancement. The larger enhancement of the photocycloreversion reaction was observed by irradiation at longer wavelength side than visible light corresponding to the LSPR frequency. 相似文献
83.
K. Matsuta Y. Masuda K. Hatanaka S. C. Jeong S. Kawasaki R. Matsumiya M. Mihara Y. Watanabe D. Nishimura Y. Morita K. Asahi T. Adachi J. Martin A. Konaka A. Miller C. Bidinosti T. Dawson L. Lee C. Davis D. Ramsay W. van Oers E. Korkmaz L. Buchman 《Hyperfine Interactions》2013,219(1-3):89-93
Polarized UCNs have been created by selecting only one spin state passing through a magnetized Fe foil. Typical degree of polarization was about 90 %. The polarization relaxation time in the prototype Ramsey cell was $T_1 =1100^{+800}_{-400}(Nd,Pr)-(Tb,Dy,Gd)-(Fe,Co,Al,Cu)-B magnets were heat treated in two different ways and investigated in the temperature range 4.2 to 400 K. After optimal heat treatment intrinsic coercive field i H c?= 1640 and 5040 kA/m for room temperature and 10 K was obtained and the temperature coefficient of remanence α?=??0.01 for temperature range 80 to 375 K was found. On basis of magnetic measurements and 57Fe Mössbauer spectroscopy, the possible reasons for the increase of i H c during multi-step heat treatment are discussed. 相似文献
84.
T. Inoue T. Furukawa A. Yoshimi Y. Ichikawa M. Chikamori Y. Ohtomo M. Tsuchiya N. Yoshida H. Shirai M. Uchida K. Suzuki T. Nanao H. Miyatake H. Ueno Y. Matsuo T. Fukuyama K. Asahi 《Hyperfine Interactions》2013,220(1-3):59-63
The present status of an active spin maser which is being developed for an experimental search for 129Xe atomic electric dipole moment (EDM) is presented. In order to realize the long term stability of maser frequency, systematic effects for the spin maser operation were investigated. The correlations in the maser frequency with the solenoid current, the environmental field and the cell temperature were found. With the solenoid current and environmental field being stabilized and the cell temperature lowered, a frequency precision of 7.9 nHz has been achieved for the maser operation. 相似文献
85.
T. Sato Y. Ichikawa S. Kojima C. Funayama S. Tanaka T. Inoue A. Uchiyama A. Gladkov A. Takamine Y. Sakamoto Y. Ohtomo C. Hirao M. Chikamori E. Hikota T. Suzuki M. Tsuchiya T. Furukawa A. Yoshimi K. Asahi 《Physics letters. A》2018,382(8):588-594
We report on the operation of co-located 129Xe and 131Xe nuclear spin masers with an external feedback scheme, and discuss the use of 131Xe as a comagnetometer in measurements of the 129Xe spin precession frequency. By applying a correction based on the observed change in the 131Xe frequency, the frequency instability due to magnetic field and cell temperature drifts are eliminated by two orders of magnitude. The frequency precision of 6.2 μHz is obtained for a 104 s averaging time, suggesting the possibility of future improvement to ≈ 1 nHz by improving the signal-to-noise ratio of the observation. 相似文献
86.
T. Nagatomo K. Shimada K. Asahi D. L. Balabanski J. M. Daugas M. Depuydt M. De Rydt L. Gaudefroy S. Grévy Y. Hasama Y. Ichikawa D. Kameda P. Morel L. Perrot C. St?del J. C. Thomas W. Vanderheijden N. Vermeulen P. Vingerhoets A. Yoshimi G. Neyens H. Ueno 《The European Physical Journal A - Hadrons and Nuclei》2009,42(3):383-385
The nuclear electric quadrupole moment (Q moment) of the neutron-rich nucleus 33Al (I = 5/2 , T 1/2 = 41 ms) has been measured by the $ \beta$ -ray detected nuclear quadrupole resonance ( $ \beta$ -NQR) method for the first time. The 33Al nucleus is considered to be on the border of the island of inversion within which a significant intrusion of the pf orbits occurs across the N = 20 shell gap and the intrusion causes an anomalous enhancement of the Q moment. Polarized 33Al nuclei were produced from 36S (77.5MeV/u beams through the fragmentation process and separated by LISE fragment separator at GANIL. The 33Al nuclei were implanted into a Al2O3 single-crystal plate and the $ \beta$ -NQR spectrum was successfully obtained. 相似文献
87.
H. Tambo S. KimuraY. Yamauchi Y. HiromuraY.K. Zhou S. EmuraS. Hasegawa H. Asahi 《Journal of Crystal Growth》2009,311(10):2962-2965
GaCrN nanorods were grown on GaN nanorods by RF-plasma-assisted molecular beam epitaxy. GaN nanorods were grown on Si (0 0 1) substrates with native SiO2. Cr doping into GaCrN nanorods was conducted at substrate temperatures of 800 and 550 °C. Cross-sectional transmission electron microscopy images revealed that the diameter of GaCrN nanorod gradually increases with growth proceeding at 550 °C, while the growth at 800 °C does not change the nanorod diameter. Low-temperature growth enhances the growth perpendicular to the c-axis and decreases the growth along the c-axis. It was found that the solubility limit of Cr atoms in GaCrN is much higher for the low-temperature growth than for the high-temperature growth. It was also found that the highest saturation magnetization is obtained at some optimum Cr cell temperature. 相似文献
88.
S. Matsuki K. Shimomura I. Ogawa K. Suzuki S. Hamada T. Nakamura H. Okuno M. Koizumi N. Inabe Y. Fukashiro H. Sunaoshi M. Wada T. Murayama T. Kohmoto M. Kitano T. Kubo T. Shinozuka K. Asahi Y. Kido T. T. Inamura T. Nomura M. Ishihara M. Fujioka H. T. Duong H. Haas 《Hyperfine Interactions》1992,74(1-4):223-239
Radiation-detected optical pumping in solids has been developed to investigate the structure of unstable nuclei. Appreciable
nuclear polarization of implanted or doped unstable-nuclei in a host crystal is achieved with the optical pumping in solids.
The nuclear polarization achieved is enhanced/reduced by applying a radio-frequency magnetic field together with the optical
pumping, radiation-detected magnetic resonance being thus observed to get information on electromagnetic properties of unstable
nuclei. Two schemes have been successfully developed for the optical pumping of unstable nuclei in solids. One is to directly
pump the atoms by the excitation from the ground state to a broad absorption band in visible and UV regions which shows a
large magnetic circular dichroism. This scheme is applicable to many rare-earth atoms in alkaline-earth fluoride host. The
other scheme is to pump the electrons in the conduction band of direct-type semiconductor and thus indirectly polarize the
nuclei in the host material via a hyperfine interaction between the nuclei and the polarized conduction electrons. This scheme
can be especially applied to the III to VI families of atoms in direct-type semiconductors. Principle of the methods, on-line
experimental system, and a few examples of the results obtained so far are presented and discussed. 相似文献
89.
90.
Osamu Suekane Shigehiko Hasegawa Masakazu Tanaka Toshiko Okui Hisao Nakashima 《Applied Surface Science》2002,190(1-4):218-221
Post-annealing effects on InAs islands grown on GaAs(0 0 1) surfaces have been investigated by scanning tunneling microscopy (STM) connected to molecular beam epitaxy (MBE). It is found that for islands grown by 1.6 ML InAs deposition at 450 °C, post-annealing at 450 °C in an As4 atmosphere causes dissolving of the InAs islands. In contrast, for larger islands obtained by 2.0 ML InAs deposition at 450 °C, the post-annealing leads to coarsening of the islands. The result can be explained in terms of a critical nucleus in heterogeneous nucleation. 相似文献