相关论文: Local moments and magnetic order in the two-dimens…
We study the interplay between electron correlation and disorder in the two-dimensional Hubbard model at half-filling by means of a variational wave function that can interpolate between Anderson and Mott insulators. We give a detailed…
In the presence of quenched disorder, the interplay between local magnetic-moment formation and Anderson localization for electrons at a zero-temperature, metal-insulator transition (MIT) remains a long unresolved problem. Here, we study…
It is shown that the Anderson-Mott metal-insulator transition of paramagnetic, interacting disordered electrons in an external magnetic field is in the same universality class as the transition from a ferromagnetic metal to a ferromagnetic…
Local magnetic moments in disordered sytems can be described in terms of annealed magnetic disorder, in addition to the underlying quenched disorder. It is shown that for noninteracting electron systems at zero temperature, the annealed…
The metal-insulator transition in correlated electron systems, where electron states transform from itinerant to localized, has been one of the central themes of condensed matter physics for more than half a century. The persistence of this…
Two-dimensional topological insulators are characterized by an insulating bulk and conductive edge states protected by the nontrivial topology of the bulk electronic structure. They remain robust against moderate disorder until Anderson…
Strong correlation effects, which are often associated to the approach to a Mott insulating state, in some cases may be observed even far from half-filling. This typically happens whenever the inter-site Coulomb repulsion induces a tendency…
Elucidating the physics of the single-orbital Hubbard model in its intermediate coupling regime is a key missing ingredient to our understanding of metal-insulator transitions in real materials. Using recent non-perturbative many-body…
It is well established that for non-interacting electrons, increasing disorder drives a metal into a gapless localized Anderson insulator. While in three dimensions a threshold in disorder must be crossed for the transition, in two…
In this overview we provide a general introduction to metal-insulator transitions, with focus on specific mechanisms that can localize the electrons in absence of magnetic or charge ordering, and produce well defined quantum critical…
The competition between the Mott transition and the Anderson localization in one dimensional electron systems is studied based upon the bosonization and the renormalization group method. The beta function is calculated up to the second…
Using a three-frequency one-dimensional kicked rotor experimentally realized with a cold atomic gas, we study the transport properties at the critical point of the metal-insulator Anderson transition. We accurately measure the…
The checkerboard lattice, with alternating 'crossed' plaquettes, serves as the two dimensional analog of the pyrochlore lattice. The corner sharing plaquette structure leads to a hugely degenerate ground state, and no magnetic order, for…
We study the magnetoresistance of two-dimensional bosonic Anderson insulators. We describe the change in spatial decay of localized excitations in response to a magnetic field, which is given by an interference sum over alternative…
Recent experiments on the amorphous magnetic semiconductor Gd_x Si_{1-x}, Phys. Rev. Lett. 77, 4652 (1996), ibid 83, 2266 (1999), ibid 84, 5411 (2000), ibid 85, 848 (2000), have revealed an insulator-metal transition (i-m-t), as a function…
The two dimensional Hubbard model in the presence of diagonal and off-diagonal disorder is studied at half filling with a finite temperature quantum Monte Carlo method. Magnetic correlations as well as the electronic compressibility are…
We investigate the metal-insulator Mott transition in a generalized version of the periodic Anderson model, in which a band of itinerant electrons is hybridrized with a narrow and strongly correlated band. Using dynamical mean-field theory,…
Magnetic moments strongly coupled to the spins of conduction electrons in a nanostructure can confine the conduction-electron motion due to scattering at almost localized Kondo singlets. We study the resulting local-moment formation in the…
The interplay between Mott and Anderson routes to localization in disordered interacting systems gives rise to different transitions and transport regimes. Here, we investigate the phase diagram at finite temperatures using dynamical mean…
The Mott-Hubbard transition is studied in the context of the two-dimensional Hubbard model. Analytical calculations show the existence of a critical value Uc of the potential strength which separates a paramagnetic metallic phase from a…