Performing the slave-boson mean-field approximation to the two-dimensional t–J model under the assumption of the uniform charge density, we find two mechanisms that lead to the breaking of fourfold symmetry of the Fermi surface (FS) and the magnetic excitation spectrum. One mechanism originates from the J-term, which has an intrinsic instability toward the formation of a quasi-one-dimensional F...

We report magnetoresistivity measurements on a La1:2Sr1:8Mn2O7 single crystal. The charge transport in the ferromagnetic phase is dominated by two-magnon scattering in the high T range and by weak localization effects at lower T ; in the non-metallic regime. In the paramagnetic phase, rabðTÞ obeys the adiabatic small polaron hopping mechanism, while rcðTÞ follows an Arrhenius behavior with the ...

Organic and polymeric semiconductor-based thin-film fieldeffect transistors (OFETs) are of great interest for low-cost largearea memories and driving circuits in display applications.1 In these organic devices, the charge carrier transport is dominated by the hopping mechanism at room temperature.2 Therefore, highly ordered thin films with large interconnected polycrystalline grains are necessa...

The pressure dependence of the Mott, spin-density-wave and superconducting instabilities of the metallic state of the Bechgaard and Fabre salts is analyzed using weak coupling scaling theory. We show how the mechanism of quantum interference between pairings in the density-wave and superconducting channels, when combined to the influence of intrachain Umklapp scattering and inter-chain hopping ...

We report for the first time on rich and tunable transport phenomena in closed-packed arrays of PbSe colloidal nanocrystals (NCs) in the form of thin films. As the interdot coupling is increased, the system evolves from an insulating regime dominated by Coulomb blockade to a semiconducting regime, where hopping conduction is the dominant transport mechanism. The observed phenomena can be interp...

The time-dependent wavepacket diffusion method for carrier quantum dynamics (Zhong and Zhao 2013 J. Chem. Phys. 138 014111), a truncated version of the stochastic Schrödinger equation/wavefunction approach that approximately satisfies the detailed balance principle and scales well with the size of the system, is applied to investigate the carrier transport in one-dimensional systems including b...

In this paper, using the theory of polynomial residue class rings, a new construction is proposed for frequency hopping patterns having optimal Hamming autocorrelation with respect to the well-known Lempel-Greenberger bound. Based on the proposed construction, many new Peng-Fan optimal families of frequency hopping sequences are obtained. The parameters of these sets of frequency hopping sequen...