3,853 research outputs found
On the Stronger Statement of Levinson's Theorem for the Dirac Equation
Recently a stronger statement of Levinson's theorem for the Dirac equation
was presented, where the limits of the phase shifts at are related to
the numbers of nodes of radial functions at the same energies, respectively.
However, in this letter we show that this statement has to be modified because
the limits of the phase shifts may be negative for the Dirac equation
Exact solution to the Schr\"{o}dinger equation for the quantum rigid body
The exact solution to the Schr\"{o}dinger equation for the rigid body with
the given angular momentum and parity is obtained. Since the quantum rigid body
can be thought of as the simplest quantum three-body problem where the internal
motion is frozen, this calculation method is a good starting point for solving
the quantum three-body problems.Comment: 8 pages, no figure, LaTex, will be published in Foundations of
Physics Letters, 12 (1999) 561-57
Matrix for
The quantum Clebsch-Gordan coefficients and the explicit form of the
matrix related with the minimal representation of the quantum
enveloping algebra are calculated in this paper
The (2+1) Dirac Equations with Potential
In this Letter the bound states of (2+1) Dirac equation with the
cylindrically symmetric -potential are discussed. It is
surprisingly found that the relation between the radial functions at two sides
of can be established by an SO(2) transformation. We obtain a
transcendental equation for calculating the energy of the bound state from the
matching condition in the configuration space. The condition for existence of
bound states is determined by the Sturm-Liouville theorem.Comment: Latex 11 pages accepted by Found. Phys. Let
Exact Solutions to the Schr\"{o}dinger Equation for the potential in 2D
Making use of an for the eigenfunctions, we obtain an exact
closed form solution to the non-relativistic Schr\"{o}dinger equation with the
anharmonic potential, in two dimensions, where
the parameters of the potential satisfy some constraints.Comment: Latex file, pages 9 and 2 eps figures, accepted by J. Phys.
The modified Seiberg-Witten monopole equations and their exact solutions
The modified Seiberg-Witten monopole equations are presented in this letter.
These equations have analytic solutions in the whole 1+3 Minkowski space with
finite energy. The physical meaning of the equations and solutions are
discussed here.Comment: RevTex, 6 page, no figur
U(2) algebraic model applied to stretching vibrational spectra of tetrahedral molecules
The highly excited stretching vibrational energy levels and the intensities
of infrared transitions in tetrahedral molecules are studied in a U(2)
algebraic model. Its applications to silane and silicon tetrafluoride are
presented with smaller standard deviations than those of other models.Comment: Revtex, 6 pages, no figure, to appear in Int. J. Theor. Phy
Exact Solutions to the Schr\"{o}dinger Equation for the Inverse-Power Potential in Two Dimensions
Utilizing an for the eigenfunctions, we arrive at an exact
closed form solution to the Schr\"{o}dinger equation with the inverse-power
potential, in two dimensions, where the
parameters of the potential satisfy a constraint.Comment: Latex file 9 pages and submit to Euro. Phys. J.
The rotational invariants constructed by the products of three spherical harmonic polynomials
The rotational invariants constructed by the products of three spherical
harmonic polynomials are expressed generally as homogeneous polynomials with
respect to the three coordinate vectors, where the coefficients are calculated
explicitly in this paper
Thermally induced structural modification in the Al/Zr multilayers
The effect of increasing temperature on the structural stability and
interactions of two kinds of Al/Zr (Al(1%wtSi)/Zr and Al(Pure)/Zr) multilayer
mirrors are investigated. All Al/Zr multilayers annealed from 200^{\circ}C to
500^{\circ}C, were deposited on Si wafers by using direct-current magnetron
sputtering technology. A detailed and consistent picture of the thermally
induced changes in the microstructure is obtained using an array of
complementary measurements including grazing incidence X-ray reflectance,
atomic force microscope, X-ray diffraction and high-resolution transmission
electron microscopy. The first significant structural changes of two systems
are observed at 250^{\circ}C, characterized by asymmetric interlayers appears
at interface. At 290^{\circ}C, the interface consisted of amorphous Al-Zr alloy
is transformed to amorphous Al-Zr alloy and cubic ZrAl3 in both systems. By
298^{\circ}C of Al(1%wtSi)/Zr and 295^{\circ}C of Al(Pure)/Zr multilayers, the
interfacial phases of Al-Zr alloy transform completely into polycrystalline
mixtures of hcp-ZrAl2 and cubic-ZrAl3, which smooth the interface boundary and
lower the surface roughness in the multilayers. Up to 500^{\circ}C, the
multilayer structure still exists in both systems, and the differences between
the asymmetric interlayers are much larger in the multilayers. Finally, we
discuss the transformation from symmetric to asymmetric in the annealing
process for other systems
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