arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1111.5878quant-phphysics.chem-ph
收藏

相干态量子中离散呼吸子的特征

Signatures of Discrete Breathers in Coherent State Quantum

Kirill Igumenshchev, Misha Ovchinnikov, Panagiotis Maniadis, Oleg Prezhdo

摘要:

离散呼吸子(DBs)--能量的空间时间周期性局部化--在大量的非线性系统中被预测。受经典力学表象和量子力学表象中DBs现象的概念性桥接的启发,我们研究了相空间中经典力学点的量子等价物--相干态--的动力学特性。我们表明,在相空间中的一个点,可以表现出无论是离域或本地化的运动相比,相干态可以显示本地化和离域行为的量子等价物的签名。在经典力学中,定域和离域运动的能量区域之间的分离是一个点。在量子力学中,这一点成为一个瞬态区,其中既有隧穿模式,也有非隧穿模式。此外,瞬态区包含不能被表征为任一模式的模式,因为从非隧穿模式到隧穿模式的过渡是平滑的。通过进一步的分析,我们记录了四个有趣的观察:1。作为耦合的函数,本征态通过避免隧道和非隧道模式之间的交叉。2.在高非线性区,隧穿模的优势被一种新的模式--高阶隧穿模的出现所削弱。这些模式类似于隧穿模式,但具有非隧穿模式的属性。...

英文摘要:

Discrete breathers (DBs) -- a spatial time-periodic localization of energy -- are predicted in a large variety of non-linear systems. Motivated by the conceptual bridging of the DBs phenomena in classical and quantum mechanical representation, we study their signatures in the dynamics of a quantum equivalent of a classical mechanical point in a phase space -- a coherent state. We show that in contrast to a point in a phase space that can exhibit either delocalized or localized motion, a coherent state can show signatures of a quantum equivalent of both localized and delocalized behavior. In classical mechanics, the separation between the energy regions of localized and delocalized motion is a point. In quantum mechanics, this point becomes a transient region, in which both tunneling and non-tunneling modes are present. Furthermore, the transient region contains modes that cannot be characterized as either, because the transition from non-tunneling to tunneling modes is smooth. With a further analysis we document four intriguing observations: 1. Considered as a function of coupling, the eigenstates go through avoided crossings between tunneling and non-tunneling modes. 2. The dominance of tunneling modes in high non-linearity region is compromised by an appearance of new types of modes -- high order tunneling modes. These modes are similar to the tunneling modes but have attributes of non-tunneling modes. ...

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。

↑