Kalla Manasa, Chebrolu Narasimha Raju, Chatterjee Ashok
School of Physics, University of Hyderabad, Hyderabad, 500046, India.
Department of Physics, Central University of Karnataka, Kalaburagi, 585367, India.
Sci Rep. 2022 Jun 8;12(1):9444. doi: 10.1038/s41598-022-13032-4.
We consider a single molecular transistor in which a quantum dot with local electron-electron and electron-phonon interactions is coupled to two metallic leads, one of which acts like a source and the other like a drain. The system is modeled by the Anderson-Holstein (AH) model. The quantum dot is mounted on a substrate that acts as a heat bath. Its phonons interact with the quantum dot phonons by the Caldeira-Leggett interaction giving rise to dissipation in the dynamics of the quantum dot system. A simple canonical transformation exactly treats the interaction of the quantum dot phonons with the substrate phonons. The electron-phonon interaction of the quantum dot is eliminated by the celebrated Lang-Firsov transformation. The time-dependent current is finally calculated by the Keldysh Green function technique with various types of bias. The transient-time phase diagram is analysed as a function of the system parameters to explore regions that can be used for fast switching in devices like nanomolecular switches.
我们考虑一个单分子晶体管，其中具有局部电子 - 电子和电子 - 声子相互作用的量子点与两个金属引线耦合，其中一个充当源极，另一个充当漏极。该系统由安德森 - 霍尔斯坦（AH）模型建模。量子点安装在充当热浴的衬底上。其声子通过卡尔德拉 - 莱格特相互作用与量子点声子相互作用，从而在量子点系统的动力学中产生耗散。一个简单的正则变换精确地处理了量子点声子与衬底声子的相互作用。量子点的电子 - 声子相互作用通过著名的朗 - 菲尔索夫变换被消除。最终通过具有各种类型偏置的凯尔迪什格林函数技术计算随时间变化的电流。作为系统参数的函数分析瞬态时间相图，以探索可用于纳米分子开关等器件中快速切换的区域。
