This title appears in the Scientific Report :
2015
Please use the identifier:
http://dx.doi.org/10.1103/PhysRevB.92.205103 in citations.
Please use the identifier: http://hdl.handle.net/2128/10785 in citations.
Finite-temperature charge transport in the one-dimensional Hubbard model
Finite-temperature charge transport in the one-dimensional Hubbard model
We study the charge conductivity of the one-dimensional repulsive Hubbard model at finite temperature using the method of dynamical quantum typicality, focusing at half filling. This numerical approach allows us to obtain current autocorrelation functions from systems with as many as 18 sites, way b...
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Personal Name(s): | Jin, F. |
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Steinigeweg, R. (Corresponding author) / Heidrich-Meisner, F. / Michielsen, K. / De Raedt, H. | |
Contributing Institute: |
Jülich Supercomputing Center; JSC |
Published in: | Physical Review B Physical review / B, 92 92 (2015 2015) 20 20, S. 205103 205103 |
Imprint: |
College Park, Md.
APS
2015
|
DOI: |
10.1103/PhysRevB.92.205103 |
Document Type: |
Journal Article |
Research Program: |
Manipulation and dynamics of quantum spin systems Computational Science and Mathematical Methods |
Link: |
OpenAccess OpenAccess |
Publikationsportal JuSER |
Please use the identifier: http://hdl.handle.net/2128/10785 in citations.
We study the charge conductivity of the one-dimensional repulsive Hubbard model at finite temperature using the method of dynamical quantum typicality, focusing at half filling. This numerical approach allows us to obtain current autocorrelation functions from systems with as many as 18 sites, way beyond the range of standard exact diagonalization. Our data clearly suggest that the charge Drude weight vanishes with a power law as a function of system size. The low-frequency dependence of the conductivity is consistent with a finite dc value and thus with diffusion, despite large finite-size effects. Furthermore, we consider the mass-imbalanced Hubbard model for which the charge Drude weight decays exponentially with system size, as expected for a nonintegrable model. We analyze the conductivity and diffusion constant as a function of the mass imbalance and we observe that the conductivity of the lighter component decreases exponentially fast with the mass-imbalance ratio. While in the extreme limit of immobile heavy particles, the Falicov-Kimball model, there is an effective Anderson-localization mechanism leading to a vanishing conductivity of the lighter species, we resolve finite conductivities for an inverse mass ratio of η≳0.25. |