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The hyperfine fields of Cr3+ and Cu2+ ions in substituted YIG were measured by NMR at 4.2 °K to be about 327 and 195 kOe, respectively. These values are rather high compared to those observed in other host lattices. Hyperfine interaction was also evaluated for Cr3+ and Cu2+ in the octahedral sites. The ionic Hamiltonian includes the crystal field energy, the spin-orbit coupling, and the exchange energy. The hyperfine fields thus estimated are in agreement with the experimental results. Es wurden die Hyperfeinfelder von in YIG substituierten Cr3+ -und Cu2+ -Ionen mit NMR bei 4,2 °K zu 327 bzw. 195 kOe gemessen. Diese Werte sind ziemlich hoch im Vergleich zu den in anderen Wirtskristallen beobachteten. Fur Cr3+ und Cu2+ an Oktaederplatzen wurde die Hyperfeinwechselwirkung berechnet. Der ionische Hamiltonian enthalt die Kristall-feldenergie, die Spin-Bahnkopplung und die Austauschenergie. Die so berechneten Hyperfeinfelder stimmen mit den experimentellen Ergebnissen uberein.

Trap parameters were evaluated from the time behaviour of space charge limited currents in Cu doped p-Si. For the Cu donor level which acts as trap in p-Si a depth EDV = 0.21 eV from the valence band and a cross section for holes S(Cu)p = 2 × 10−14 cm2 were obtained. No temperature variation of cross section could be observed in the temperature range between 78 and 120 °K. Es wird uber Ermittlungen von Haftstellenparametern aus der Zeitabhangigkeit von raumladungsbegrenzten Stromen bei Cu-dotiertem Silizium berichtet. Fur das in p-Si als Haftzentrum wirksame Donatorniveau von Cu wurde die energetische Lage zum Valenzband zu EDV = 0,21 eV und der Lochereinfangquerschnitt zu S(Cu)p = 2 × 10−14 cm2 bestimmt. Im Temperaturbereich von 78 bis 120 °K konnte kein Temperaturgang des Wirkungsquerschnitts beobachtet werden.

Phase relationships in the CdP 2 -Sn system have been determined. CdSnP 2 forms peritectically at approximately 570°C and crystals of this semiconductor can be grown successfully from tin solutions containing CdP 2 concentrations of less than 10 mole percent. Some electrical and optical results on Ag and Cu doped crystals are presented.

Copper-doped InSb films were grown by the controlled recrystallization from the liquid phase of their composite elemental constituents. The magnetic field and temperature dependence of their transverse magnetoresistance and Hall coefficient are analyzed in terms of a two-band conduction process. It is shown that grain boundary scattering which limits the electron mobility below that of the bulk material, has a negligible effect on the hole mobility above 200°K.

Optical absorption measurements in the band gap region of pure and Cu doped ZnO single crystals have been performed at temperatures from 77 K to 500 K. The broadening of the absorption is considered to be caused by electric microfields from ionized impurities, LO-phonon and piezoelectric LA-phonons. The microfields are calculated as function of temperature and doping and it is shown that acoustic phonons are of importance in forming the Urbach tail.