656 research outputs found
Effects of hydrostatic pressure on the mechanical behavior of body centered cubic refractory metals and alloys
Hydrostatic pressure on mechanical behavior of body centered cubic refractory metals and alloy
Effects of hydrostatic pressure on the mechanical behavior of body centered cubic refractory metals and alloys Interim technical report
Effects of hydrostatic pressure on mechanical behavior of body centered cubic refractory metals and alloy
Effects of hydrostatic pressure on the mechanical behavior of body centered cubic refractory metals and alloys Interim technical report no. 3
Effects of hydrostatic pressure on mechanical properties of tungsten, tungsten-thorium alloys, and iron-carbon alloy
Effects of hydrostatic pressure on the mechanical behavior of body centered cubic refractory metals and alloys Interim technical report no. 4, 1 Jun. 1965 - 1 Jun. 1966
Hydrostatic pressure effect on mechanical behavior of body centered cubic refractory metals and alloy
Two-photon excitation and relaxation of the 3d-4d resonance in atomic Kr
Two-photon excitation of a single-photon forbidden Auger resonance has been observed and investigated using the intense extreme ultraviolet radiation from the free electron laser in Hamburg. At the wavelength 26.9 nm (46 eV) two photons promoted a 3d core electron to the outer 4d shell. The subsequent Auger decay, as well as several nonlinear above threshold ionization processes, were studied by electron spectroscopy. The experimental data are in excellent agreement with theoretical predictions and analysis of the underlying multiphoton processes
Critical behavior of thermopower and conductivity at the metal-insulator transition in high-mobility Si-MOSFET's
This letter reports thermopower and conductivity measurements through the
metal-insulator transition for 2-dimensional electron gases in high mobility
Si-MOSFET's. At low temperatures both thermopower and conductivity show
critical behavior as a function of electron density which is very similar to
that expected for an Anderson transition. In particular, when approaching the
critical density from the metallic side the diffusion thermopower appears to
diverge and the conductivity vanishes. On the insulating side the thermopower
shows an upturn with decreasing temperature.Comment: 4 pages with 3 figure
Geometric approach to nonlinear coherent states using the Higgs model for harmonic oscillator
In this paper, we investigate the relation between the curvature of the
physical space and the deformation function of the deformed oscillator algebra
using non-linear coherent states approach. For this purpose, we study
two-dimensional harmonic oscillators on the flat surface and on a sphere by
applying the Higgs modell. With the use of their algebras, we show that the
two-dimensional oscillator algebra on a surface can be considered as a deformed
one-dimensional oscillator algebra where the effect of the curvature of the
surface is appeared as a deformation function. We also show that the curvature
of the physical space plays the role of deformation parameter. Then we
construct the associated coherent states on the flat surface and on a sphere
and compare their quantum statistical properties, including quadrature
squeezing and antibunching effect.Comment: 12 pages, 7 figs. To be appeared in J. Phys.
On the semiclassical treatment of anharmonic quantum oscillators via coherent states - The Toda chain revisited
We use coherent states as a time-dependent variational ansatz for a
semiclassical treatment of the dynamics of anharmonic quantum oscillators. In
this approach the square variance of the Hamiltonian within coherent states is
of particular interest. This quantity turns out to have natural interpretation
with respect to time-dependent solutions of the semiclassical equations of
motion. Moreover, our approach allows for an estimate of the decoherence time
of a classical object due to quantum fluctuations. We illustrate our findings
at the example of the Toda chain.Comment: 12 pages, some remarks added. Version to be published in J. Phys. A:
Math. Ge
Algebraic analysis of a model of two-dimensional gravity
An algebraic analysis of the Hamiltonian formulation of the model
two-dimensional gravity is performed. The crucial fact is an exact coincidence
of the Poisson brackets algebra of the secondary constraints of this
Hamiltonian formulation with the SO(2,1)-algebra. The eigenvectors of the
canonical Hamiltonian are obtained and explicitly written in closed
form.Comment: 21 pages, to appear in General Relativity and Gravitatio
Monge Distance between Quantum States
We define a metric in the space of quantum states taking the Monge distance
between corresponding Husimi distributions (Q--functions). This quantity
fulfills the axioms of a metric and satisfies the following semiclassical
property: the distance between two coherent states is equal to the Euclidean
distance between corresponding points in the classical phase space. We compute
analytically distances between certain states (coherent, squeezed, Fock and
thermal) and discuss a scheme for numerical computation of Monge distance for
two arbitrary quantum states.Comment: 9 pages in LaTex - RevTex + 2 figures in ps. submitted to Phys. Rev.
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