The normal-state energy spectrum of the two-dimensional $t$ - $J$ model in a homogeneous perpendicular magnetic field is investigated. The density of states at the Fermi level as a function of the inverse magnetic field $\frac{1}{B}$ reveals oscillations in the range of hole concentrations $0.08The normal-state energy spectrum of the two-dimensional $t$-$J$ model in a homogeneous perpendicular magnetic field is investigated. The density of states at the Fermi level as a function of the inverse magnetic field $\frac{1}{B}$ reveals oscillations in the range of hole concentrations $0.08

arXiv:1311.0374Nov 2, 20130 citations

The t-J Model in a Strong Magnetic Field

A. Sherman

The normal-state energy spectrum of the two-dimensional t-J model in a homogeneous perpendicular magnetic eld B is investigated using the Mori projection operator technique.The density of states at the Fermi level as a function of 1/B reveals both high-and low-frequency oscillations.The high-frequency oscillations correspond to large Fermi surfaces, while the low-frequency components are related to van Hove singularities in the Landau subbands, which stem from their bending due to strong electron correlations.Frequencies of the low-frequency components are of the same order of magnitude as those observed in underdoped cuprates.These components become dominant if smoothing processes are involved.It is shown that despite increased distances between subbands the pseudogap aects only slightly the frequency of density of states oscillations.The normal-state energy spectrum of the two-dimensional t-J model in a homogeneous perpendicular magnetic eld B is investigated using the Mori projection operator technique.The density of states at the Fermi level as a function of 1/B reveals both high-and low-frequency oscillations.The high-frequency oscillations correspond to large Fermi surfaces, while the low-frequency components are related to van Hove singularities in the Landau subbands, which stem from their bending due to strong electron correlations.Frequencies of the low-frequency components are of the same order of magnitude as those observed in underdoped cuprates.These components become dominant if smoothing processes are involved.It is shown that despite increased distances between subbands the pseudogap aects only slightly the frequency of density of states oscillations.

Acta Physica Polonica AFeb 1, 20150 citations

Quantum phenomena in strongly correlated electron systems

Pavel V. Shevchenko

Sep 1, 19990 citations

Gap Formation in the Symmetric Periodic Anderson Model in Infinite Dimensions. II

Tetsuya Mutou, Dai S. Hirashima

We study dymanical properties of the symmetric periodic Anderson model in infinite dimensions by applying the quantum Monte Carlo method and the maximum entropy method. It is found that at low temperatures a gap is developed in the density of states, in the local spin excitation spectrum and in the local charge excitation spectrum. We clarify the effects of the strong electron correlation on structure of these dynamical quantities. As the strength of interaction increases, a sharp peak evolves at a low frequency region in the spin excitation spectrum while a broad shoulder appears at a higher frequency. On the other hand, as the interaction gets strong, the charge excitation spectrum splits into a low-frequency part and a high-frequency part; the low frequency part is severely suppressed by the interaction. The reliability and the limitation of the maximum entropy method are also discussed in detail.We study dymanical properties of the symmetric periodic Anderson model in infinite dimensions by applying the quantum Monte Carlo method and the maximum entropy method. It is found that at low temperatures a gap is developed in the density of states, in the local spin excitation spectrum and in the local charge excitation spectrum. We clarify the effects of the strong electron correlation on structure of these dynamical quantities. As the strength of interaction increases, a sharp peak evolves at a low frequency region in the spin excitation spectrum while a broad shoulder appears at a higher frequency. On the other hand, as the interaction gets strong, the charge excitation spectrum splits into a low-frequency part and a high-frequency part; the low frequency part is severely suppressed by the interaction. The reliability and the limitation of the maximum entropy method are also discussed in detail.

Journal of the Physical Society of JapanDec 15, 199516 citations

Quantum fluctuations in correlated electron systems

Nayana Shah

Jan 1, 20030 citations

The normal-state energy spectrum of the two-dimensional

t

J

model in a homogeneous perpendicular magnetic field is investigated. The density of states at the Fermi level as a function of the inverse magnetic field

\frac{1}{B}

reveals oscillations in the range of hole concentrations $0.08