Asymmetry induces long-lasting energy current transients inside molecular loop circuits

Fabienne Michelini (1) , Katawoura Beltako (1)

1 IM2NP - Institut des Matériaux, de Microélectronique et des Nanosciences de Provence

Energy transport and conversion at nanoscale have become an important topic of fundamental and applied research, in particular for conceiving groundbreaking solutions in energy-aware digital electronics and energy production. In this work, we propose a formal framework to address time-dependent energy transport inside quantum networks. The approach permits us to investigate how energy transferred to electrons by a femtosecond laser pulse is stored and released in a molecular circuit consisting of two donor-acceptor branches connected to an acceptor chain. Additionally, the two donors may be coupled, creating a loop inside the circuit. Time-resolved analysis reveals that when a difference exists between the two donor-acceptor branches, a loop current occurs and persists during relaxation, while only a small amount of current flows through the acceptor chain. A long-lasting energy flow thus emerges from the asymmetry of the molecular structure.

Domains: Physics [physics]; Condensed Matter [cond-mat]; Mesoscopic Systems and Quantum Hall Effect [cond-mat.mes-hall]; Physics [physics]; Quantum Physics [quant-ph]

Fabienne Michelini, Katawoura Beltako. Asymmetry induces long-lasting energy current transients inside molecular loop circuits. Physical Review B: Condensed Matter (1978-1997), 2019, pp.024308. ⟨10.1103/PhysRevB.100.024308⟩. ⟨hal-03019045⟩