摘要:

AbstractIn the temperature range 1.65 to 300 K the temperature dependence of the electron mobility is studied in n‐ZnSe crystals with a concentration of electrically active impurities ranging from 7 × 1015to 5 × 1018cm−3and a compensation degree of 0.16 to 0.98. The anomalously low values of the electron mobility and its sharp change with temperature by a power law with an exponent 2 to 4 in heavily doped strongly compensated crystals are accounted for by the specific character of conductivity and Hall effect in samples with a random large scale impurity potential rather than by the peculiarities of the electron scattering. The dependence of the electron mobility on the concentration and the degree of impurity compensation is st

ISSN:0370-1972    

DOI:10.1002/pssb.2221360138

出版商:WILEY‐VCH Verlag    

年代:1986

数据来源: WILEY

摘要:

AbstractThe free energy of a superconductor in the presence of a sinusoidal (helical) magnetic order is considered. The method of projection is used to diagonalyze the electronic Hamiltonian. The wavelength 2π/Qof the sinusoidal (helical) phase of amplitudeMis computed self‐consistently. A reduction of the cooper pair,M2/Q, is found which stabilizes the sinusoidal pha

ISSN:0370-1972    

DOI:10.1002/pssb.2221360139

出版商:WILEY‐VCH Verlag    

年代:1986

数据来源: WILEY

摘要:

AbstractA temperature induced metal (M) → insulator (I) transition is investigated which is possibly first of its kind in the titanium rich titanium disulphide crystals confirming to the composition Ti1.17S2. This transition is established by monitoring the temperature dependence of the electrical conductivity and the thermoelectric power. The structural characteristics at room temperature and at high temperatures (≈ 573 K) also are explored through electron diffraction. The M → I transition is believed tooccur due to the increase of disorder which occurs at high temperature where the short range order state of excess Ti atoms in the van der Waals gapgives rise to a highly disordered amorphous like state. This may lead toshifting of the mobility edge from below the Fermi energy to above the Fermienergy, thus leading to the observed M → I tra

ISSN:0370-1972    

DOI:10.1002/pssb.2221360140

出版商:WILEY‐VCH Verlag    

年代:1986

数据来源: WILEY

摘要:

AbstractPiezoresistivity measurements are carried out on heavily doped ion‐implanted p‐type resistors on the surfaces of cantilever beams cut from a (100) silicon wafer. Tensile and compressive stresses, up to 85 MPa along the [110] direction, are applied by bending the beams with a micrometer. Nonlinear effects are clearly seen in the measurements where the resistor contains sections both parallel and perpendicular to the stress. The results are analyzed in terms of the first‐ and second‐order piezoresistance coefficients. Values of the piezoresistance coefficients are calculated using analytical expressions for the strain dependent energy‐wave vector relations of the valence bands and the known deformation potentials. The results of the calculations are compared with the experimental data including some earlier measurements reported in literature. The calculated values of the first‐order coefficients are found to agree fairly well with the experimental data. The calculated second‐order coefficients are able to describe the observed anisotropy in the nonlinear piezoresistivity of the second or

ISSN:0370-1972    

DOI:10.1002/pssb.2221360141

出版商:WILEY‐VCH Verlag    

年代:1986

数据来源: WILEY

摘要:

AbstractA superconducting Hamiltonian is considered in which both intraband and interband pairing interactions are included. This Hamiltonian is recast in a form suitable for the study of heavy fermion superconductivity (HFS). The superconducting transition temperatureTcis calculated and some characteristic features of HFS explained. Effects of interband pairing interaction are discussed.

ISSN:0370-1972    

DOI:10.1002/pssb.2221360142

出版商:WILEY‐VCH Verlag    

年代:1986

数据来源: WILEY

摘要:

AbstractThe effect of temperature and coupling strength on the thermoelectric power of the small‐polaron hopping disordered regime is investigated. The thermoelectric power is evaluated for the high‐and low‐temperature case assuming the electron‐lattice interaction to be weak. Results are also given for the low‐temperature and strong‐coupling case. The “macroscopic” thermoelectric power of the material is evaluated for the low‐t

ISSN:0370-1972    

DOI:10.1002/pssb.2221360143

出版商:WILEY‐VCH Verlag    

年代:1986

数据来源: WILEY

ISSN:0370-1972    

DOI:10.1002/pssb.2221360101

出版商:WILEY‐VCH Verlag    

年代:1986

数据来源: WILEY