Project A6:
Transport through quantum dots out of equilibrium (2009-2013)
Summary
The aim of this project is to study electrical transport through quantum dots beyond linear response theory, i.e. with a finite bias, in situations where strong correlations dominate. The numerical studies should be carried out by means of the time-dependent Density Matrix Renormalization Group (t-DMRG) method. The results obtained are expected to be instrumental for the quantum control of complex quantum dot systems.
We plan in this project to extend our previous studies of nonequilibrium dynamics of strongly correlated systems by means of t-DMRG within the project B4, to electrical transport through complex quantum dot systems out of equilibrium. Specifically, we will focus our attention on systems with quantum dots interacting by common electronic reservoirs. In the case of two quantum dots in the Kondo regime coupled by a common lead, the different situations arising from the competition between the Kondo scale and the Ruderman-Kittel-Kasuya-Yoshida (RKKY) interaction should be studied. This problem is of interest not only in the field of mesoscopic systems but also for heavy fermion compounds, and hence, of general interest in condensed matter physics. The configurations will be adapted to the ones studied in project A1.
Going beyond single quantum dots to interacting ones, we expect to uncover new aspects of the dynamics of such complex systems and to find the routes to tailor the corresponding new states. In particular, by explicitly including the dynamics in the leads, and modeling the interaction within them, the effects of decoherence of the states in the dots can be followed out of equilibrium. Due to the flexibility of the t-DMRG method, also more complex situations including several quantum dots and an increasing number of electrons can be considered.
Project leaders
Prof. Dr. Alejandro Muramatsu, Institut für Theoretische Physik III, Universität Stuttgart
Refs & Publications
A. Moreno, A. Muramatsu, and J. M. P. Carmelo"Charge and spin fractionalization beyond the Luttinger-liquid paradigm"
Phys. Rev. B 87, 075101 (2013); doi: 10.1103/PhysRevB.87.075101
E. Canovi, A. Moreno, and A. Muramatsu
"Transport through two interacting resonant levels connected by a Fermi sea"
Phys. Rev. B., 88, 245105 (2013); arXiv:1301.7683 [cond-mat.str-el]; doi: 10.1103/PhysRevB.88.245105
A. Moreno, A. Muramatsu, and S. R. Manmana
"Ground-state phase diagram of the one-dimensional t-J model"
Phys. Rev. B 83, 205113 (2011); doi: 10.1103/PhysRevB.83.205113
F. Heidrich-Meisner, S. R. Manmana, M. Rigol, A. Muramatsu, A. E. Feiguin, and E. Dagotto
"Quantum distillation: Dynamical generation of low-entropy states of strongly correlated fermions in an optical lattice"
Phys. Rev. A 80, 041603(R) (2009); doi: 10.1103/PhysRevA.80.041603
S.R. Manmana, S. Wessel, R.M. Noack, and A. Muramatsu
"Time evolution of correlations in strongly interacting fermions after a quantum quench"
Phys. Rev. B 79, 155104 (2009); doi: 10.1103/PhysRevB.79.155104