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51.
We demonstrate that one can exhaustively determine the n‐bound eigenstates of a Hamiltonian H by constructing a sequence of supersymmetric (SUSY) partner Hamiltonians and invoking a time‐dependent quantum adiabatic switching algorithm for passage from the ground state of one to the other. The ground states of the initial pair H(0) and H(1) are constructed by solving the Riccati equation for the superpotential ?(0) for H(0) and adiabatically switching from the ground state Ψ of H(0) to the ground state Ψ of H(1). The charge operator Q is then used to recover the first excited state Ψ of H(0). The procedure is repeated for the ground states of SUSY pairs H(n + 1) and H(n + 2), and appropriate charge operators lead to the excited states Ψ of H(0) with , thereby exhausting the full eigenspectrum of H(0). The workability of the proposed method is shown with several well‐known examples. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2011 相似文献
52.
In this paper an Eulerian rate-dependent single crystal model that accounts for high-strain rates, large strains and rotations is developed. The viscoplastic law as well as the evolution equations for the lattice are written in terms of vectorial and tensorial quantities associated with the current configuration. The viscoplastic law is obtained from Schmid law using an overstress approach. Such an expression for the viscoplastic law is motivated by the microdynamics of crystal defects. A general analysis of the plane-strain response of the proposed rigid-viscoplastic single crystal model is presented. It is shown that only one differential equation, involving the orientation of one composite in-plane slip system, is necessary to describe the lattice evolution. Several two-dimensional boundary value problems, such as equal-channel die extrusion and channel die compression are selected to illustrate the predictive capabilities of the model. The results show that even at relatively low strain rates the viscosity plays an important role in the development of localized deformation modes. At high crosshead velocity, the plastic properties and crystal anisotropy are less important while inertia effects are dominant. Finally, the grains interaction is investigated by analyzing the compression of a grains multicrystal. 相似文献
53.
MO Xiao-Hu 《中国物理C(英文版)》2010,34(11):1671-1679
The kinematic properties of two-body decay near τ threshold are studied according to the special capacity of the BEPC accelerator and the BESⅢ detector.Explicitly presented are the transformations of energy and momentum of hadronic particles between different reference frames,and the corresponding distributions.A brand new method is proposed to obtain the energy spread of the accelerator by fitting the energy distribution of hadron from τ semi-leptonic decays. 相似文献
54.
We calculate the cross section for neutralino annihilation into the two-photon and apply the cross section to find the flux in a γ-ray telescope such
as ASTROGAM. The processes
\tilde{χ}10
\tilde{χ}10→
γγ may be astrophysically significant sources of γ-ray lines. The theoretical estimates of diffuse γ-ray background are subject to uncertainties. 相似文献
55.
In this paper, we propose a supersymmetric SU(1|2) Gaudin model and have derived its eigenvalues. We also present the well-defined eigenstates through the quasi-classical limit of the eigenstates in the supersymmetric t-J model. 相似文献
56.
三维各向同性谐振子的超对称量子力学体系 总被引:3,自引:3,他引:0
利用三维各向同性谐振子的中升、降算子,分别构造不同的超对称量子力学体系,并研究了它们的性质。 相似文献
57.
QIAN Shang-Wu MIAO Chun-Hui GU Zhi-Yu 《理论物理通讯》2006,46(1):37-38
This article uses the supersymmetric WKB approximation to obtain the approximate energy levels and wave functions of the anharmonic potential V(r) = ar^2 + br^-4 + cr^-6 in order to tesify the correctness between [Phys. Left. A 170 (1992) 335] and the paper written by M. Landtman [Phys. Left. A 175 (1993) 147]. 相似文献
58.
WANG Xue-Lei LI Ji-Tao LIU Su-Zhen 《理论物理通讯》2007,48(5):891-894
In the minimal supersymmetric standard model with R-parity violation, the lepton number violating top quark interactions can contribute to the top pair production at a linear collider via tree-level u-channel squark exchange diagrams. We calculate such contributions and find that in the allowed range of these R-violating couplings, the top pair production rate as well as the top quark polarization and the forward-backward asymmetry can be significantly altered. By comparing the unpolarized beams with the polarized beams, we find that the polarized beams are more powerful in probing such new physics. 相似文献
59.
We investigate the lepton flavor violation processes pp→eμX induced by R-parity violating interactions at the
Tevatron hadron collider. The theoretical calculation and Monte
Carlo simulation demonstrate that with a set of suitable cuts on
experimental observables, one might be capable to reduce the
standard model physical background to a controllable level so that
the signals of R-parity violating interactions could be detected
distinctively. Furthermore, clear sneutrino information can be
abstracted from the purified event sample where other SUSY scalar
quark ``pollution' is heavily suppressed. We conclude that with a
reasonable assumption of 10 fb-1 integrated luminosity, the
experiments at the Tevatron machine would have potential to
discover sneutrino in the region of
m_{\tilde{ν}}≤400 GeV via
lepton flavor violation eμ production channels, or extend the
mass scale constraint up to m_{\tilde{ν}}≥ 550 GeV at 95% CL. 相似文献
60.
Based on supersymmetric quantum mechanics theory, we introduced
a supersymmetric unitary transformation to diagonalize the Hamiltonian
of non-degenerate two-mode two-photon Jaynes-Cummings models
which include any forms of intensity-dependent coupling, field-dependent
detuning, and field nonlinearity. Its
eigenvalue, eigenstates, and time evolution of state vector are
obtained. 相似文献