Bipolaron binding in quantum wires

Article

关键词: STRONG-COUPLING LIMIT;    3 DIMENSIONS;    MAGNETIC-FIELD;    MULTILAYER STRUCTURES;    STABILITY;    POLARON;    STATES;    WELLS;   

DOI  :  10.1103/PhysRevB.61.2721

来源: SCIE

【 摘 要 】

A theory of bipolaron states in quantum wires with a parabolic potential well is developed applying the Feynman variational principle. The basic parameters of the bipolaron ground state (the binding energy, the number of phonons in the bipolaron cloud, the effective mass, and the bipolaron radius) are studied as a function of sizes of the potential well. Two cases are considered in detail: a cylindrical quantum wire and a planar quantum wire. Analytical expressions for the bipolaron parameters are obtained at large and small sizes of the quantum well. It is shown that at R much greater than 1 [where R means the radius (half width) of a cylindrical (planar) quantum wire, expressed in Feynman units], the influence of confinement on the bipolaron binding energy is described by the function similar to 1/R-2 for both cases, while at small sizes this influence is different in each case. In quantum wires, the bipolaron binding energy W(R) increases logarithmically with decreasing radius. The shapes and the sizes of a nanostructure, which are favorable for observation of stable bipolaron states, are determined.

【 授权许可】

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