277 research outputs found
Semiconductor materials for IR optoelectronics
Based on studies at the State Institute of Applied Optics Scientific Manufacturing Organization, this review discusses the main properties of III-V, IV-VI, and II-VI narrow-band compounds and solid solutions, as well as the properties of doped germanium and silicon. The use of these materials in IR sources and detectors is considered, along with their use as optical media for optoelectronic devices (filters, modulators, elements for integrated optics and gradient optics, etc.). © 1996 The Optical Society of America
Hall helps Ohm: some corrections to negative-U centers approach to transport properties of YBaCuO and LaSrCuO
For broad oxygen and strontium doping ranges, temperature dependences
(T-dependences) of the normal state resistivity \rho(T) of YBa_2Cu_3O_x (YBCO)
and La_(2-x)Sr_xCuO_4 (LSCO) are calculated and compared to experiments. Holes
transport was taken in the \tau-approximation, where \tau(T,\epsilon) is due to
acoustic phonons. Besides, T-dependence of the chemical potential \mu(T) and
effective carrier mass m* ~10-100 free electron masses, obtained by negative-U
centers modelling the T-dependence of the Hall coefficient, were used to
calculate \rho(T). In addition, it is demonstrated that anisotropy of the
cuprates does not affect the calculated T-variation of neither Hall coefficient
nor \rho, but only rescale their magnitudes by factors depending on
combinations of m_ab and m_c.Comment: 4th International Conference Fundamental Problems of High-Temperature
Superconductivity, Moscow-Zvenigorod (October 3-7, 2011) Submitted to J.
Supercond. Nov. Magn.: after revision. Extension for Supercond. Sci. Technol.
24 075026 (2011), DOI: 10.1088/0953-2048/24/7/075026 Contains: 2 pages, 3
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