Jorn Ryan, Seideman Tamar
Department of Chemistry, Northwestern University, Evanston, Illinois 60208, USA.
J Chem Phys. 2008 Nov 21;129(19):194703. doi: 10.1063/1.2977954.
A recently developed theory that formulates the phenomena of inelastic transport and current-driven dynamics in molecular-scale electronics within a time-dependent scattering approach is extended to account for dissipation of the current-induced excitation through coupling to electrode phonons and electron-hole pairs. Our approach treats the electronic transport, the nuclear dynamics, and the energy and phase exchange between the electronic and the vibrational subspaces in the course of the inelastic scattering event within the Schrodinger picture, whereas the dissipation of the energy deposited in the nuclear modes is accounted for within a density matrix approach. Subsequent to formulation of the theory in terms of population relaxation and phase decoherence rates, we develop approaches for computing these rates, treating on equal footing the dissipation due to excitation of electron-hole pairs and that due to the interaction with phonons. Finally, we test the derived rates by application to the model problem of CO adsorbed on metal surfaces, an example that has been extensively studied previously and for which several experimental results are available for comparison.
一种最近发展的理论，该理论在含时散射方法中阐述了分子尺度电子学中的非弹性输运和电流驱动动力学现象，现被扩展以考虑通过与电极声子和电子 - 空穴对耦合导致的电流诱导激发的耗散。我们的方法在薛定谔绘景中处理非弹性散射事件过程中的电子输运、核动力学以及电子和振动子空间之间的能量和相位交换，而沉积在核模式中的能量耗散则在密度矩阵方法中予以考虑。在根据布居弛豫和相位退相干率表述该理论之后，我们开发了计算这些率的方法，平等对待由于电子 - 空穴对激发以及与声子相互作用导致的耗散。最后，我们通过将其应用于吸附在金属表面的CO的模型问题来检验推导得到的率，这是一个先前已被广泛研究且有多个实验结果可供比较的例子。
