Electron transport through molecules: A new kind of open quantum system theory

Supervisors: Drs Brendon Lovett (St Andrews) and Eric Gauger (Heriot Watt)

Controlling how electrons flow through molecular structures is key to designing future miniaturised electronic components [1]. Understanding and manipulating such charge transport is a very challenging problem at this nanoscopic scale, especially in the common situation of strong interactions between the charges carriers and the vibrational mode structure of the environment [2]. In this project, you will develop such an understanding using advanced techniques for simulating open quantum systems. We have recently developed a groundbreaking new theoretical method [3] which relies on a combination of Feynman path integrals and matrix product states, and which opens up the possibility of a multitude of new calculations. The tool that you will develop will be a significant adaptation of this new method, and will describe any quantum problem in which a small system is coupled to both bosonic and fermionic environments. We hope to reveal new insights into how electron currents in molecules behave, and this will allow us to design new molecular devices that exploit quantum coherence. [1] S. V. Aradhya and L. Venkataraman, Nat. Nanotechnol. 8 399 (2013). [2] J. Sowa, J. A. Mol, G. A. D. Briggs, and E. M. Gauger, The Journal of Chemical Physics 149 in press (2018); arXiv:1807.08502 [3] A. Strathearn, P. Kirton, D. Kilda, J. Keeling, and B. W. Lovett. , Nature Communications 9 3322 (2018)