Solving the Jaynes-Cummings Model with Shift Operators Constructed by Means of the Matrix-Diagonalizing Technique

The Jaynes-Cummings model is solved with the raising and lowering(shift) operators using the matrix-diagonalizing technique. Bell nonlocality is also found to be present ubiquitously in the excitation states of the model.     

Non-degenerate single-particle energies in the Ginocchio model

A one-body operator expressing the breaking of the degeneracy of the single-nucleon energies is added to the pairing interaction of the Ginocchio model. This operator couples states inside the model's SD space to states outside it. The influence of this coupling on the effective interaction in the SD space and the possibility of expressing the results in terms of renormalization of parameters in the fermion hamiltonian or the IBM are investigated. The effective interaction is found to be almost diagonal in seniority, while splitting the previously-degenerate seniority multiplets. Appropriately renormalized Ginocchio and IBM hamiltonians can approximately reproduce the results, but fermion-number dependence of the hamiltonian parameters and explicit three-body interactions are needed to reproduce the computed effects exactly.     

Path integral treatment for the generalized Ginocchio potentials

The solution for the generalized Ginocchio potentials is exactly constructed by the path integral approach combined to the summation of the spectral representation. The energy spectrum and the wave functions of bound and scattering states are explicitly evaluated. The scattering functionS _l for each angular momentuml is also deduced.     

Geometric Phase in a Generalized Jaynes-Cummings Model with Double Mode Operators and Phase Operators

By using of the invariant theory, we have studied the geometric phase of quantum dots in the time-dependent isotropic magnetic field, the dynamical and geometric phases are given, respectively.     

Common Shift Operators of {H,L2} for N-Dimensional Harmonic Oscillator

The common shift operators of {H, L²} for N-dimensional harmonic oscillator are established.     

The Nonlinear Eigenfrequency Shift in QGP

The kinetic equations for quark-gluon plasma (QGP) are studied beyond the linear response theory, and the nonlinear eigenfrequency shift owing to the non-Abelian interaction of the color eigenmodes in a spatially uniform QGP is calculated.     

Dynamical Model and Path Integral Formalism for Hubbard Operators

In this paper, the possibility to construct apath integral formalism by using the Hubbard operatorsas field dynamical variables is investigated. By meansof arguments coming from the Faddeev-Jackiw symplectic Lagrangian formalism as well as from theHamiltonian Dirac method, it can be shown that it is notpossible to define a classical dynamics consistent withthe full algebra of the Hubbard X-operators. Moreover, from the Faddeev-Jackiw symplectic algorithm,and in order to satisfy the Hubbard X-operatorscommutation rules, it is possible to determine thenumber of constraints that must be included in aclassical dynamical model. Following this approach, it isclear how the constraint conditions that must beintroduced in the classical Lagrangian formulation areweaker than the constraint conditions imposed by the full Hubbard operators algebra. The consequenceof this fact is analyzed in the context of the pathintegral formalism. Finally, in the framework of theperturbative theory, the diagrammatic and the Feynman rules of the model are discussed.     

Hidden Grassmann Structure in the XXZ Model II: Creation Operators

In this article we unveil a new structure in the space of operators of the XXZ chain. For each α we consider the space of all quasi-local operators, which are products of the disorder field with arbitrary local operators. In analogy with CFT the disorder operator itself is considered as primary field. In our previous paper, we have introduced the annhilation operators b(ζ), c(ζ) which mutually anti-commute and kill the “primary field”. Here we construct the creation counterpart b*(ζ), c*(ζ) and prove the canonical anti-commutation relations with the annihilation operators. We conjecture that the creation operators mutually anti-commute, thereby upgrading the Grassmann structure to the fermionic structure. The bosonic operator t*(ζ) is the generating function of the adjoint action by local integrals of motion, and commutes entirely with the fermionic creation and annihilation operators. Operators b*(ζ), c*(ζ), t*(ζ) create quasi-local operators starting from the primary field. We show that the ground state averages of quasi-local operators created in this way are given by determinants. Membre du CNRS On leave of absence from Skobeltsyn Institute of Nuclear Physics, MSU, 119992 Moscow, Russia Dedicated to the memory of Alexei Zamolodchikov     

Anderson Localization for Schrödinger Operators on ℤ with Potentials Given by the Skew–Shift

In this paper we study one-dimensional Schr?dinger operators on the lattice with a potential given by the skew shift. We show that Anderson localization takes place for most phases and frequencies and sufficiently large disorders. Received: 19 September 2000 / Accepted: 15 February 2001     

The Geometry of Recursion Operators

We study the fields of endomorphisms intertwining pairs of symplectic structures. Using these endomorphisms we prove an analogue of Moser’s theorem for simultaneous isotopies of two families of symplectic forms. We also consider the geometric structures defined by pairs and triples of symplectic forms for which the squares of the intertwining endomorphisms are plus or minus the identity. For pairs of forms we recover the notions of symplectic pairs and of holomorphic symplectic structures. For triples we recover the notion of a hypersymplectic structure, and we also find three new structures that have not been considered before. One of these is the symplectic formulation of hyper-Kähler geometry, which turns out to be a strict generalization of the usual definition in terms of differential or Kähler geometry.     

Vertex Operators – From a Toy Model to Lattice Algebras

Within the framework of the discrete Wess–Zumino–Novikov–Witten theory we analyze the structure of vertex operators on a lattice. In particular, the lattice analogues of operator product expansions and braid relations are discussed. As the main physical application, a rigorous construction for the discrete counterpart g _n $ of the group valued field g(x) is provided. We study several automorphisms of the lattice algebras including discretizations of the evolution in the WZNW model. Our analysis is based on the theory of modular Hopf algebras and its formulation in terms of universal elements. Algebras of vertex operators and their structure constants are obtained for the deformed universal enveloping algebras . Throughout the whole paper, the abelian WZNW model is used as a simple example to illustrate the steps of our construction. Received: 16 December 1996 / Accepted: 5 May 1997     

Inverse of Radiation Field Operators and the Generalized Jaynes-Cummings Model

We generalize the standard Jaynes-Cummings model (JCM) to a model Hamiltonian with the radiation field operators being the inverse of a harmonic oscillator's creation and annihilation operators. Some new commutative relations about the inverse operators are derived and the generalized JCM Hamiltonian's eigenstates are derived.     

Exact Solution for a Multiphoton Generalized Jaynes-Cummings Model with Inverse Operators

A new exactly solvable multiphoton generalized Jaynes-Cummings model is presented, whose Hamiltonian is related to the inverse of field mode creation and annihilation operators. Then we use supersymmetric unitary operators to diagonalize the Hamiltonian above and obtain their energy spectra and eigenstates. In addition, its pseudo-invariant eigen-operator is found as well, directly leading to the corresponding energy-level gap.     

The Invertible Double of Elliptic Operators

First, we review the Dirac operator folklore about basic analytic and geometrical properties of operators of Dirac type on compact manifolds with smooth boundary and on closed partitioned manifolds and show how these properties depend on the construction of a canonical invertible double and are related to the concept of the Calderón projection. Then we summarize a recent construction of a canonical invertible double for general first order elliptic differential operators over smooth compact manifolds with boundary. We derive a natural formula for the Calderón projection which yields a generalization of the famous Cobordism Theorem. We provide a list of assumptions to obtain a continuous variation of the Calderón projection under smooth variation of the coefficients. That yields various new spectral flow theorems. Finally, we sketch a research program for confining, respectively closing, the last remaining gaps between the geometric Dirac operator type situation and the general linear elliptic case.     

Logarithmic Intertwining Operators and Vertex Operators

This is the first in a series of papers where we study logarithmic intertwining operators for various vertex subalgebras of Heisenberg and lattice vertex algebras. In this paper we examine logarithmic intertwining operators associated with rank one Heisenberg vertex operator algebra M(1) _a , of central charge 1 − 12a ². We classify these operators in terms of depth and provide explicit constructions in all cases. Our intertwining operators resemble puncture operators appearing in quantum Liouville field theory. Furthermore, for a = 0 we focus on the vertex operator subalgebra L(1, 0) of M(1)₀ and obtain logarithmic intertwining operators among indecomposable Virasoro algebra modules. In particular, we construct explicitly a family of hidden logarithmic intertwining operators, i.e., those that operate among two ordinary and one genuine logarithmic L(1, 0)-module.     

Properties of Linear Entropy in k-Photon Jaynes-Cummings Model with Stark Shift and Kerr-Like Medium

The time evolution of the linear entropy of an taking into consideration Stark shift and Kerr-like medium. atom in k-photon daynes-Cummings model is investigated The effect of both the Stark shift and Kerr-like medium on the linear entropy is analyzed using a numerical technique for the field initially in coherent state and in even coherent state. The results show that the presence of the Kerr-like medium and Stark shift has an important effect on the properties of the entropy and entanglement. It is also shown that the setting of the initial state plays a significant role in the evolution of the linear entropy and entanglement.     

InxGa1-xN薄膜的弯曲因子及斯托克斯移动研究

采用常压金属有机化学汽相沉积(MOCVD)技术以Al2O3为衬底在GaN膜上生长了InxGa1-xN薄膜。以卢瑟福背散射／沟道技术、光透射谱、光致发光光谱对InxGa1-xN／GaN／AI2O3样品进行了测试。研究了InxGa1-xN薄膜的弯曲因子及斯托克斯移动。结果表明，采用光透射谱、光致发光光谱得到的InxGa1-xN薄膜的禁带宽度一致，InxGa1-xN薄膜并不存在斯托克斯移动。InxGa1-xN薄膜的In组分分别为0．04，0．06，0．24，0．26时，其弯曲因子分别为3．40,2．36，1．82，3．70。随In组分变化。InxGa1-xN薄膜的弯曲因子的变化并没有一定的规律，表明InxGa1-xN薄膜的禁带宽度随In组分的变化关系复杂。     

The Dirac Equation in Coordinates and the Red Shift

The Dirac equation of the general relativity theory, written immediately in coordinates, is used to find the spectrum of a hydrogenlike atom in the Schwarzschild field.     

The Born-Oppenheimer Approximation to the Wave Operators

We apply the Born-Oppenheimer approximation to a scattering problem. We consider a diatomic molecule with short-range potential separating into two atoms. Using our earlier mathematicd results we construct a leading order expansion to the wave operator for this scattering channel. We comment on limitation and possible extensions of this work.