Describing non-Hermitian dynamics using a Generalized Three-Time NEGF for a Partition-free Molecular Junction with Electron-Phonon Coupling

• URL: http://arxiv.org/abs/2108.05133v1
• Date: Wed, 11 Aug 2021 10:19:31 GMT
• Title: Describing non-Hermitian dynamics using a Generalized Three-Time NEGF for a Partition-free Molecular Junction with Electron-Phonon Coupling
• Authors: Matthew A Lane and Lev Kantorovich
• Abstract summary: We develop the Non-Equilibrium Green's Function formalism for a dissipative molecular junction. Our approach is partitionless and valid for an external bias with arbitrary time dependence.
• Score: 0.0
• License: http://creativecommons.org/licenses/by/4.0/
• Abstract: In this paper we develop the Non-Equilibrium Green's Function (NEGF) formalism for a dissipative molecular junction that consists of a central molecular system with one-dimensional electronic transport coupled to a phonon environment and attached to multiple electronic leads. Our approach is partitionless - initial preparation of the system places the whole system in the correct canonical equilibrium state - and is valid for an external bias with arbitrary time dependence. Using path integrals as an intermediary tool, we apply a two-time Hubbard-Stratonovich transformation to the phonon influence functional with mixed real and imaginary times to obtain an exact expression for the electronic density matrix at the expense of introducing coloured Gaussian noises whose properties are rigorously derived from the environment action. This results in a unique stochastic Hamiltonian on each branch of the Konstantinov-Perel' contour (upper, lower, vertical) such that the time evolution operators in the Liouville equation no longer form a Hermitian conjugate pair, thus corresponding to non-Hermitian dynamics. To account for this we develop a generalized three-time NEGF which is sensitive to all branches of the contour, and relate it to the standard NEGF in the absence of phonons via a perturbative expansion of the noises. This approach is exact and fully general, describing the non-equilibrium driven dynamics from an initial thermal state while subject to inelastic scattering, and can be applied to non-Hermitian dynamics in general.

Related papers

• Entanglement dynamics from universal low-lying modes [0.0]
  Information-theoretic quantities such as Renyi entropies show a remarkable universality in their late-time behaviour. We provide evidence that in systems with no symmetries, the low-energy excitations of the Euclidean Hamiltonian are universally given by a gapped quasiparticle-like band. This structure provides an understanding of entanglement dynamics in terms of a universal set of gapped low-lying modes.
  arXiv  Detail & Related papers  (2024-07-23T18:00:16Z)
• Non-Hermitian Fermi-Dirac Distribution in Persistent Current Transport [0.0]
  Persistent currents circulate continuously without requiring external power sources. We introduce a non-Hermitian Fermi-Dirac distribution and derive an analytical expression for the persistent current that relies solely on the complex spectrum. We show that the persistent currents in both systems exhibit no anomalies at any emergent exceptional points, whose signatures are only discernible in the current susceptibility.
  arXiv  Detail & Related papers  (2024-03-14T17:00:00Z)
• Dynamics of inhomogeneous spin ensembles with all-to-all interactions: breaking permutational invariance [49.1574468325115]
  We investigate the consequences of introducing non-uniform initial conditions in the dynamics of spin ensembles characterized by all-to-all interactions. We find that the dynamics of the spin ensemble now spans a more expansive effective Hilbert space.
  arXiv  Detail & Related papers  (2023-09-19T16:44:14Z)
• Slow semiclassical dynamics of a two-dimensional Hubbard model in disorder-free potentials [77.34726150561087]
  We show that introduction of harmonic and spin-dependent linear potentials sufficiently validates fTWA for longer times. In particular, we focus on a finite two-dimensional system and show that at intermediate linear potential strength, the addition of a harmonic potential and spin dependence of the tilt, results in subdiffusive dynamics.
  arXiv  Detail & Related papers  (2022-10-03T16:51:25Z)
• A dynamical theory for one-dimensional fermions with strong two-body losses: universal non-Hermitian Zeno physics and spin-charge separation [0.0]
  We study an interacting one-dimensional gas of spin-1/2 fermions with two-body losses. We show how the two non-equilibrium evolutions build up drastically different charge correlations.
  arXiv  Detail & Related papers  (2022-06-14T13:31:33Z)
• Photoinduced prethermal order parameter dynamics in the two-dimensional large-$N$ Hubbard-Heisenberg model [77.34726150561087]
  We study the microscopic dynamics of competing ordered phases in a two-dimensional correlated electron model. We simulate the light-induced transition between two competing phases.
  arXiv  Detail & Related papers  (2022-05-13T13:13:31Z)
• Non-Gaussian superradiant transition via three-body ultrastrong coupling [62.997667081978825]
  We introduce a class of quantum optical Hamiltonian characterized by three-body couplings. We propose a circuit-QED scheme based on state-of-the-art technology that implements the considered model.
  arXiv  Detail & Related papers  (2022-04-07T15:39:21Z)
• Simultaneous Transport Evolution for Minimax Equilibria on Measures [48.82838283786807]
  Min-max optimization problems arise in several key machine learning setups, including adversarial learning and generative modeling. In this work we focus instead in finding mixed equilibria, and consider the associated lifted problem in the space of probability measures. By adding entropic regularization, our main result establishes global convergence towards the global equilibrium.
  arXiv  Detail & Related papers  (2022-02-14T02:23:16Z)
• Probing non-Hermitian phase transitions in curved space via quench dynamics [0.0]
  Non-Hermitian Hamiltonians are relevant to describe the features of a broad class of physical phenomena. We study the interplay of geometry and non-Hermitian dynamics by unveiling the existence of curvature-dependent non-Hermitian phase transitions.
  arXiv  Detail & Related papers  (2020-12-14T19:47:59Z)
• Dynamical preparation of a steady ODLRO state in the Hubbard model with local non-Hermitian impurity [0.0]
  We show that the non-Hermitian Hubbard Hamiltonian can respect a full real spectrum even if a local non-Hermitian impurity is applied to. Our results lay the groundwork for the dynamical generation of a steady ODLRO state through the critical non-Hermitian strongly correlated system.
  arXiv  Detail & Related papers  (2020-09-14T03:05:38Z)
• Analog cosmological reheating in an ultracold Bose gas [58.720142291102135]
  We quantum-simulate the reheating-like dynamics of a generic cosmological single-field model in an ultracold Bose gas. Expanding spacetime as well as the background oscillating inflaton field are mimicked in the non-relativistic limit. The proposed experiment has the potential of exploring the evolution up to late times even beyond the weak coupling regime.
  arXiv  Detail & Related papers  (2020-08-05T18:00:26Z)

This list is automatically generated from the titles and abstracts of the papers in this site.

This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.