Non-equilibrium dynamics of quantum heat transport in nanoscale devices


DPG Frühjahrstagung der Sektion Kondensierte Materie (SKM) | event contribution
March 16, 2018 | Berlin, Germany

Next to electrons, phonons play a major role for the behavior of nanoscale devices. Additionally, phononics and nano-mechanics offer the possibility to steer and manipulate phonons. Hence, a more detailed understanding of phonon dynamics is required. Using an auxiliary-mode approach, which has successfully been applied for the case of electrons [1], we present a method to describe time-dependent phonon transport based on the time evolution of the phonon density matrix. We compute the phonon density matrix by employing the non-equilibrium Greens function formalism. This method allows us to gain insight into the behavior of local vibrations which are driven by time-dependent temperature differences between heat reservoirs [2,3]. In the present work, we apply this methodology to study the time dependence of the thermal current in molecular junctions. [1] B. S. Popescu and A. Croy, New J. Phys. 18, 093044, (2016). [2] R. Tuovinen et al., Phys. Rev. B 93, 214301, (2016). [3] Marcone I. Sena-Junior et al., J. Phys. A: Math. Theor. 50, 435202, (2017)


Authors

Non-equilibrium dynamics of quantum heat transport in nanoscale devices


DPG Frühjahrstagung der Sektion Kondensierte Materie (SKM) | event contribution
March 16, 2018 | Berlin, Germany

Next to electrons, phonons play a major role for the behavior of nanoscale devices. Additionally, phononics and nano-mechanics offer the possibility to steer and manipulate phonons. Hence, a more detailed understanding of phonon dynamics is required. Using an auxiliary-mode approach, which has successfully been applied for the case of electrons [1], we present a method to describe time-dependent phonon transport based on the time evolution of the phonon density matrix. We compute the phonon density matrix by employing the non-equilibrium Greens function formalism. This method allows us to gain insight into the behavior of local vibrations which are driven by time-dependent temperature differences between heat reservoirs [2,3]. In the present work, we apply this methodology to study the time dependence of the thermal current in molecular junctions. [1] B. S. Popescu and A. Croy, New J. Phys. 18, 093044, (2016). [2] R. Tuovinen et al., Phys. Rev. B 93, 214301, (2016). [3] Marcone I. Sena-Junior et al., J. Phys. A: Math. Theor. 50, 435202, (2017)


Authors