THEORY OF MANY-BOSON SYSTEMS: PAIR THEORY
THEORY OF MANY-BOSON SYSTEMS: PAIR THEORY
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多玻色子系统理论：配对理论
DOI：
10.1103/physrev.113.755
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发表时间：
1959
期刊：
影响因子：
--
通讯作者：
R. Arnowitt
中科院分区：
文献类型：
--
作者：
M. Girardeau;R. Arnowitt
具有排斥相互作用的多玻色子系统采用基于指数对激发型变分试验状态的变分方法进行处理，该变分试验状态是通过Bogoliubov的推广而获得的；该处理与配对的中间耦合近似密切相关。推导了确定变分基态的非线性积分方程，并检查了该基态和相关激发态的各种性质。由此产生的低位光谱低于博戈柳博夫的光谱，其数量与粒子总数成正比。变分原理被证明可以为哈密顿量的配对部分产生严格的能量特征值差异。然而，变分态仍然表现出对激发态的非物理特征：对相关函数在零粒子分离时不会变为零，并且声子谱在基态之上呈现出间隙。建议可以通过使用考虑两个以上粒子的动量守恒基团的激发的状态来消除这些特征。 （授权）
The many-boson system with repulsive interactions is treated by a variational method based on a variational trial state of an exponential pair- excitation type obtained by a generalization of that of Bogoliubov; the treatment is closely related to an intermediate-coupling approximation with respect to pairs. The nonlinear integral equation which determines the variational ground state is derived, and various properties of this ground state and the associated excited states are examined. The resultant low-lying spectrum lies below that of Bogoliubov by an amount proportional to the total number of particles. The variational principle is shown to produce rigorous energy eigenvalue differences for the pair part of the Hamiltonian. The variational states, however, still exhibit unphysical features characteristic of pair-excitation states: The pair correlation function does not go to zero at zero particle separation and the phonon spectrum exhibits a gap above the ground state. It is suggested that these features can be removed by using states which take into account excitation of momentum-conserving groups of more than two particles. (auth)