arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1909.04136quant-phmath-phmath.MP
收藏

由达布变换产生的精确可解含时振子的相干态

Coherent states for exactly solvable time-dependent oscillators generated by Darboux transformations

Sara Cruz y Cruz, Ruben Razo, Oscar Rosas-Ortiz, Kevin Zelaya

摘要:

在量子力学中,达布方法通常用于坐标变量,以产生新的精确可解(定态)势。在这项工作中,我们遵循Bagrov,Samsonov和Shekoyan(BSS)引入的变化,包括时间变量作为参数的变换。新的潜力是非平稳的,并定义哈密顿量,这不是积分的运动系统的研究。我们用定常频率的定常振子来产生非定常振子,并提供一个不变量来唯一地定义系统的状态。在这个意义上说,我们的方法完成了BSS方法的程序,因为不变量的本征函数是相关薛定谔方程的解的空间的正交基。当同时计算所涉及的函数时,正交正规性成立。非定常振子的动力学代数是由适当选择的梯形算子生成的,与海森堡代数一致。我们还构建了相关的相干态,并表明它们形成了一个过完备集,最大限度地减少了由梯形算子定义的求积。这些状态在时间演化下不是不变的,因为它们的时间依赖性依赖于状态的基础,而不是标记它们的复本征值。提供了一些具体的例子。

英文摘要:

The Darboux method is commonly used in the coordinate variable to produce new exactly solvable (stationary) potentials in quantum mechanics. In this work we follow a variation introduced by Bagrov, Samsonov, and Shekoyan (BSS) to include the time-variable as a parameter of the transformation. The new potentials are nonstationary and define Hamiltonians which are not integrals of motion for the system under study. We take the stationary oscillator of constant frequency to produce nonstationary oscillators, and also provide an invariant that serves to define uniquely the state of the system. In this sense our approach completes the program of the BSS method since the eigenfunctions of the invariant are an orthonormal basis for the space of solutions of the related Schrodinger equation. The orthonormality holds when the involved functions are evaluated at the same time. The dynamical algebra of the nonstationary oscillators is generated by properly chosen ladder operators and coincides with the Heisenberg algebra. We also construct the related coherent states and show that they form an overcomplete set that minimizes the quadratures defined by the ladder operators. These states are not invariant under time-evolution since their time-dependence relies on the basis of states and not on the complex eigenvalue that labels them. Some concrete examples are provided.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑