scholarly journals Polaron dynamics with off-diagonal coupling: beyond the Ehrenfest approximation

2017 ◽  
Vol 19 (2) ◽  
pp. 1655-1668 ◽  
Author(s):  
Zhongkai Huang ◽  
Lu Wang ◽  
Changqin Wu ◽  
Lipeng Chen ◽  
Frank Grossmann ◽  
...  
Keyword(s):  
Variational Principle ◽  
Molecular Crystal ◽  
Time Dependent ◽  
Phonon Coupling ◽  
One Dimensional ◽  
Crystal Model ◽  
Polaron Dynamics ◽  
Diagonal Coupling

Treated traditionally by the Ehrenfest approximation, the dynamics of a one-dimensional molecular crystal model with off-diagonal exciton–phonon coupling is investigated in this work using the Dirac–Frenkel time-dependent variational principle with the multi-D2Ansatz.

scholarly journals Polaron features of the one-dimensional Holstein molecular crystal model

2000 ◽  
Vol 62 (3) ◽  
pp. 1496-1499 ◽  
Author(s):  
V. Cataudella ◽  
G. De Filippis ◽  
G. Iadonisi
Keyword(s):  
Molecular Crystal ◽  
One Dimensional ◽  
Crystal Model ◽  
The One

scholarly journals Hamiltonian Approach to Magnetic Fields with Toroidal Surfaces

1985 ◽  
Vol 40 (10) ◽  
pp. 959-967
Author(s):  
A. Salat
Keyword(s):  
Magnetic Field ◽  
Hamiltonian System ◽  
Magnetic Fields ◽  
Constant Pressure ◽  
Time Dependent ◽  
Hamiltonian Approach ◽  
One Dimensional ◽  
Mhd Equilibrium ◽  
Magnetic Surfaces ◽  
Rotational Transform

The equivalence of magnetic field line equations to a one-dimensional time-dependent Hamiltonian system is used to construct magnetic fields with arbitrary toroidal magnetic surfaces I = const. For this purpose Hamiltonians H which together with their invariants satisfy periodicity constraints have to be known. The choice of H fixes the rotational transform η(I). Arbitrary axisymmetric fields, and nonaxisymmetric fields with constant η(I) are considered in detail.Configurations with coinciding magnetic and current density surfaces are obtained. The approach used is not well suited, however, to satisfying the additional MHD equilibrium condition of constant pressure on magnetic surfaces.

Sign in / Sign up

Export Citation Format

Share Document