8,865 research outputs found
Analysis and optimization of an omnidirectional direction-finding system
System determines the direction of arrival of an electromagnetic wave with the direction information in a readily usable form. It presents a relatively small physical structure and does not require mechanical positioning
Investigation of the kinetics of crystallization of molten binary and ternary oxide systems Quarterly status report, 1 Mar. - 30 Nov. 1968
Glass composition preparation and research on crystallization kinetics of molten binary and ternary oxide systems of glas
Investigation of the kinetics of crystallization of molten binary and ternary oxide systems Quarterly status report, 1 Dec. 1967 - 29 Feb. 1968
Reaction kinetics of crystallized molten binary and ternary oxide glass making composition
Mapping the spin-dependent electron reflectivity of Fe and Co ferromagnetic thin films
Spin Polarized Low Energy Electron Microscopy is used as a spin dependent
spectroscopic probe to study the spin dependent specular reflection of a
polarized electron beam from two different magnetic thin film systems:
Fe/W(110) and Co/W(110). The reflectivity and spin-dependent
exchange-scattering asymmetry are studied as a function of electron kinetic
energy and film thickness, as well as the time dependence. The largest value of
the figure of merit for spin polarimetry is observed for a 5 monolayer thick
film of Co/W(110) at an electron kinetic energy of 2eV. This value is 2 orders
of magnitude higher than previously obtained with state of the art Mini-Mott
polarimeter. We discuss implications of our results for the development of an
electron-spin-polarimeter using the exchange-interaction at low energy.Comment: 5 pages, 4 figure
Strong correlation effects and optical conductivity in electron doped cuprates
We demonstrate that most features ascribed to strong correlation effects in
various spectroscopies of the cuprates are captured by a calculation of the
self-energy incorporating effects of spin and charge fluctuations. The self
energy is calculated over the full doping range of electron-doped cuprates from
half filling to the overdoped system. The spectral function reveals four
subbands, two widely split incoherent bands representing the remnant of the
split Hubbard bands, and two additional coherent, spin- and charge-dressed
in-gap bands split by a spin-density wave, which collapses in the overdoped
regime. The incoherent features persist to high doping, producing a remnant
Mott gap in the optical spectra, while transitions between the in-gap states
lead to pseudogap features in the mid-infrared.Comment: 5 pages, 4 figure
Josephson effect in point contacts between ''f-wave'' superconductors
A stationary Josephson effect in point contacts between triplet
superconductors is analyzed theoretically for most probable models of the order
parameter in UPt_{3} and Sr_{2}RuO_{4}. The consequence of misorientation of
crystals in superconducting banks on this effect is considered. We show that
different models for the order parameter lead to quite different current-phase
dependences. For certain angles of misorientation a boundary between
superconductors can generate the parallel to surface spontaneous current. In a
number of cases the state with a zero Josephson current and minimum of the free
energy corresponds to a spontaneous phase difference. This phase difference
depends on the misorientation angle and may possess any value. We conclude that
experimental investigations of the current-phase dependences of small junctions
can be used for determination of the order parameter symmetry in the mentioned
above superconductors.Comment: 11 pages, 8 figure
- …