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Luttinger liquid universality in the time evolution after an interaction quench
We provide strong evidence that the relaxation dynamics of one-dimensional,
metallic Fermi systems resulting out of an abrupt amplitude change of the
two-particle interaction has aspects which are universal in the Luttinger
liquid sense: The leading long-time behavior of certain observables is
described by universal functions of the equilibrium Luttinger liquid parameter
and the renormalized velocity. We analytically derive those functions for the
Tomonaga-Luttinger model and verify our hypothesis of universality by
considering spinless lattice fermions within the framework of the density
matrix renormalization group
Non-equilibrium effects on charge and energy partitioning after an interaction quench
Charge and energy fractionalization are among the most intriguing features of
interacting onedimensional fermion systems. In this work we determine how these
phenomena are modified in the presence of an interaction quench. Charge and
energy are injected into the system suddenly after the quench, by means of
tunneling processes with a non-interacting one-dimensional probe. Here, we
demonstrate that the system settles to a steady state in which the charge
fractionalization ratio is unaffected by the pre-quenched parameters. On the
contrary, due to the post-quench nonequilibrium spectral function, the energy
partitioning ratio is strongly modified, reaching values larger than one. This
is a peculiar feature of the non-equilibrium dynamics of the quench process and
it is in sharp contrast with the non-quenched case, where the ratio is bounded
by one.Comment: 12 pages, 4 figure
Nonthermal steady states after an interaction quench in the Falicov-Kimball model
We present the exact solution of the Falicov-Kimball model after a sudden
change of its interaction parameter using non-equilibrium dynamical mean-field
theory. For different interaction quenches between the homogeneous metallic and
insulating phases the system relaxes to a non-thermal steady state on time
scales on the order of hbar/bandwidth, showing collapse and revival with an
approximate period of h/interaction if the interaction is large. We discuss the
reasons for this behavior and provide a statistical description of the final
steady state by means of generalized Gibbs ensembles.Comment: 4 pages, 2 figures; published versio
Finite element analysis of temperature distribution using ABAQUS for a laser based tile grout sealing process
Interaction of CO2, Nd:YAG, excimer and high power diode laser (HPDL) radiation with the surface of an Al2O3/SiO2 based ceramic was found to effect significant changes in the wettability characteristics of the material. It was observed that interaction with CO2, Nd:YAG and HPDL radiation reduced the enamel contact angle from 1180 to 310, 340 and 330 respectively. In contrast, interaction with excimer laser radiation resulted an increase in the contact angle to 1210. Such changes were identified as being due to: (i) the melting and partial vitrification of the Al2O3/SiO2 based ceramic surface as a result of interaction with CO2, Nd:YAG HPDL radiation. (ii) the surface roughness of the Al2O3/SiO2 based ceramic increasing after interaction with excimer laser radiation. (iii) the surface oxygen content of the Al2O3/SiO2 based ceramic increasing after interaction with CO2, Nd:YAG and HPDL radiation. The work has shown that the wettability characteristics of the Al2O3/SiO2 based ceramic could be controlled and/or modified with laser surface treatment. In particular, whether the laser radiation had the propensity to cause surface melting. However, a wavelength dependance of the change of the wetting properties could not be deduced from the findings of this work
Surface glazing of concrete using a 2.5 kW high power diode lase
Interaction of CO2, Nd:YAG, excimer and high power diode laser (HPDL) radiation with the surface of an Al2O3/SiO2 based ceramic was found to affect significant changes in the wettability characteristics of the material. It was observed that interaction with CO2, Nd:YAG and HPDL radiation reduced the enamel contact angle from 1180 to 310, 340 and 330 respectively. In contrast, interaction with excimer laser radiation resulted an increase in the contact angle to 1210. Such changes were identified as being due to: (i) the melting and partial vitrification of the Al2O3/SiO2 based ceramic surface as a result of interaction with CO2, Nd:YAG HPDL radiation. (ii) the surface roughness of the Al2O3/SiO2 based ceramic increasing after interaction with excimer laser radiation. (iii) the relative surface oxygen content of the Al2O3/SiO2 based ceramic increasing after interaction with CO2, Nd:YAG and HPDL radiation. The work has shown that the wettability characteristics of the Al2O3/SiO2 based ceramic could be controlled and/or modified with laser surface treatment. Moreover, it was found that changes in the wettability characteristics of the Al2O3/SiO2 based ceramic are related to the effects of laser wavelength, that is whether the wavelength of the laser radiation has the propensity to cause surface melting
Fermionisation dynamics of a strongly interacting 1D Bose gas after an interaction quench
We study the dynamics of a one-dimensional Bose gas after a sudden change of
the interaction strength from zero to a finite value using the numerical
time-evolving block decimation (TEBD) algorithm. It is shown that despite the
integrability of the system, local quantities such as the two-particle
correlation attain steady state values in a short characteristic
time inversely proportional to the Tonks parameter and the square of
the density. The asymptotic values are very close to those of a finite
temperature grand canonical ensemble with a local temperature corresponding to
initial energy and density. Non-local density-density correlations on the other
hand approach a steady state on a much larger time scale determined by the
finite propagation velocity of oscillatory correlation waves.Comment: 11 pages, 5 figures, extende
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