This title appears in the Scientific Report :
2014
Please use the identifier:
http://dx.doi.org/10.1103/PhysRevB.90.094417 in citations.
Please use the identifier: http://hdl.handle.net/2128/8098 in citations.
Scaling of diffusion constants in the spin-$\frac{1}{2}$ XX ladder
Scaling of diffusion constants in the spin-$\frac{1}{2}$ XX ladder
We study the dynamics of spin currents in the spin-$\frac{1}{2}$ XX ladder at finite temperature. Within linear response theory, we numerically calculate autocorrelation functions for quantum systems larger than what is accessible with exact diagonalization using the concept of dynamical quantum typ...
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Personal Name(s): | Steinigeweg, R. (Corresponding Author) |
---|---|
Heidrich-Meisner, F. / Gemmer, J. / Michielsen, K. / De Raedt, H. | |
Contributing Institute: |
Jülich Supercomputing Center; JSC |
Published in: | Physical Review B Physical review / B, 90 90 (2014 2014) 9 9, S. 094417 094417 |
Imprint: |
College Park, Md.
APS
2014
|
DOI: |
10.1103/PhysRevB.90.094417 |
Document Type: |
Journal Article |
Research Program: |
Computational Science and Mathematical Methods |
Link: |
OpenAccess |
Publikationsportal JuSER |
Please use the identifier: http://hdl.handle.net/2128/8098 in citations.
We study the dynamics of spin currents in the spin-$\frac{1}{2}$ XX ladder at finite temperature. Within linear response theory, we numerically calculate autocorrelation functions for quantum systems larger than what is accessible with exact diagonalization using the concept of dynamical quantum typicality. While the spin Drude weight vanishes exponentially quickly with increasing system size, we show that this model realizes standard diffusive dynamics. Moreover, we unveil the existence of three qualitatively different dependencies of the spin-diffusion coefficient on the rung-coupling strength, resulting from a crossover from exponential to Gaussian dissipation as the rung coupling increases, in agreement with analytical predictions. We further discuss the implications of our results for experiments with cold atomic gases. |