Using non-equilibrium molecular dynamics, we show that asymmetrically defected graphene nanoribbons (GNR) are promising thermal rectifiers. The optimum conditions for thermal rectification (TR) include low temperature, high temperature bias, 1% concentration of single-vacancy or substitutional silicon defects, and a moderate partition of the pristine and defected regions. TR ratio of 80% is fou...

We have simulated the classical Heisenberg antiferromagnet on a triangular lattice using a local Monte Carlo algorithm. The behavior of the correlation length ξ, the susceptibility at the ordering wavevector χ(Q), and the spin stiffness ρ clearly reflects the existence of two temperature regimes – a high temperature regime T > Tth, in which the disordering effect of vortices is dominant, and a ...

We consider the semi-infinite q–state Potts model. We prove, for large q, the existence of a first order surface phase transition between the ordered phase and the the so-called “new low temperature phase” predicted in [27], in which the bulk is ordered whereas the surface is disordered.

We consider microscopically low-temperature transport in weakly disordered arrays of Josephson junctions in the Coulomb blockade regime. We demonstrate that at sufficiently low temperatures the main contribution to the dc conductivity comes from the motion of single-Cooper-pair excitations, scattered by irregularities in the array. Being proportional to the concentration of the excitations, the...

We study an integrable model of one-dimensional strongly correlated electrons at finite temperature by explicit calculation of the correlation lengths of various correlation functions. The model is invariant with respect to the quantum superalgebra Uq(sl(2|1)) and characterized by the Hubbard interaction, correlated hopping and pair-hopping terms. Using the integrability, the graded quantum tra...

We report on a study of the dynamics of decoherence of a matter-wave interferometer, consisting of a pair of low-dimensional cold atom condensates at finite temperature. We identify two distinct regimes in the time dependence of the coherence factor of the interferometer: quantum and classical. Explicit analytical results are obtained in both regimes. In particular, in the two-dimensional case ...

High-resolution ac calorimetry has been carried out on dispersions of aerosils in the liquid crystal octyloxycyanobiphenyl (8OCB) as a function of aerosil concentration and temperature spanning the crystal to isotropic phases. The liquid crystal 8OCB is elastically stiffer than the previously well studied octylcyanobiphenyl (8CB)+aerosil system and so general quenched random-disorder effects an...

Contrary to pyramids and domes, elongated huts on a Si(001) substrate are commonly considered as kinetically limited structures. In this work, however, based on detailed scanning tunneling microscopy observations of Ge huts growing on Si(001) at temperatures below 550 degrees C and finite element analysis, the possibility of an equilibrium-driven elongation is raised, where hut-preceding pits a...

Anomalous Hall effect (AHE) of a ferromagnetic semiconductor anatase Ti1−xCoxO2−δ thin film is studied from 10 K to 300 K. Magnetic field dependence of anomalous Hall resistance is coincident with that of magnetization, while the anomalous Hall resistance decreases at low temperature in spite of nearly temperature-independent magnetization. Anomalous Hall conductivity σAHE is found to be propor...

The objective of this work is to investigate the spray ignition characteristics of diesel and canola-derived biodiesel in a rapid compression machine at the low temperatures (676 816 K) and reduced oxygen concentrations (12 and 18%) that are used in low-temperature combustion strategies of advanced diesel engines. A method for testing ignition delay times and apparent heat release rates at a se...