Related papers: Enhancement of persistent current in a non-Hermiti…
The exact solutions of the complete Dirac equation for fermions moving in ideal Aharonov-Bohm rings are used for deriving the exact expressions of the relativistic partial currents. It is show that as in the non-relativistic case these…
Using an exact diagonalization technique within a generalized Mott-Hubbard Hamiltonian, we predict the existence of a ground state persistent current in coherent two-dimensional semiconductor quantum dot arrays pierced by an external…
Due to their iconic linearly vanishing density of states near the zero-energy, half-filled two-dimensional Dirac materials in flat Euclidean and negatively-curved hyperbolic spaces exhibit dynamic mass generation only once a critical…
We consider an extended Hubbard model of interacting fermions on a lattice. The fermion kinetic energy corresponds to a tight binding Hamiltonian with nearest neighbour (-t) and next nearest neighbour (t') hopping matrix elements. In…
We describe a "train" effect which may exist in small metallic and semiconductor rings and might be associated with the long-standing problem of the persistent current enhancement. The current is associated with the cooperative motion of N…
We study the effects of local perturbations on the dynamics of disordered fermionic systems in order to characterize time-irreversibility. We focus on three different systems, the non-interacting Anderson and Aubry-Andr\'e-Harper (AAH-)…
We study the correlated Haldane-Hubbard model with single-particle gain and loss, focusing on its non-Hermitian phase diagram and the ensuing non-unitary dynamic properties. The interplay of interactions and non-hermiticity results in…
Non-Hermitian effects could create rich dynamical and topological phase structures. In this work, we show that the collaboration between lattice dimerization and non-Hermiticity could generally bring about mobility edges and multiple…
We study the two-dimensional paramagnetic Anderson-Hubbard model using an extension of dynamical mean-field theory that allows us to treat disorder and strong electronic correlations on equal footing. We investigate the scaling of the…
We present a detailed, quantitative study of the competition between interaction- and disorder-induced effects in electronic systems. For this the Anderson-Hubbard model with diagonal disorder is investigated analytically and by Quantum…
In this work we study non-Hermitian extensions of the paradigmatic spin-1/2 XY chain in a magnetic field. Using the mapping of the model to free fermion form, we provide analytical insights into the energy spectrum of the non-Hermitian…
We demonstrate that persistent currents can be induced in a quantum system in contact with a structured reservoir, without the need of any applied gauge field. The working principle of the mechanism leading to their presence is based on the…
The interaction of a discrete state coupled to a continuum is a longstanding problem of major interest in different areas of quantum and classical physics. In Hermitian models, several dynamical decoupling schemes have been suggested, in…
We show that several novel effects related to persistent currents can arise in open systems, which have no analogue in closed or isolated systems. We have considered a system of a metallic ring coupled to two electron reservoirs. We show…
The effect of non-equilibrium constraints and dephasing on the circulating currents in molecular junctions are analyzed. Circulating currents are manifestations of quantum effects and can be induced either by externally applied bias or an…
In order for non-Hermitian (NH) topological effects to be relevant for practical applications, it is necessary to study disordered systems. In the absence of disorder, certain driven-dissipative cavity arrays with engineered non-local…
The non-Hermitian systems exhibit extreme sensitivity to the boundary conditions. The change in the eigenspectrum with tunning boundary parameter is intimately connected to the non-Hermitian skin effect. The single-particle systems are…
We present an extensive analytical study of persistent current in a weakly disordered two-chain cylindrical ring threaded by an Aharonov-Bohm flux $0 < \phi <\phi_0/2$ (with $\phi_0$ the flux quantum) and described by the Anderson model.…
Non-Hermitian Hamiltonians are relevant to describe the features of a broad class of physical phenomena, ranging from photonics and atomic and molecular systems to nuclear physics and mesoscopic electronic systems. An important question…
Effects of Coulomb interaction on persistent currents in disordered one-dimensional rings are numerically investigated. First of all effectiveness of the Hartree-Fock approximation is established on small systems. Then the calculations are…