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Related papers: Critical dislocation speed in helium-4 crystals

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We derive the ratio of transport and single particle relaxation times in three and two - dimensional electron gases due to scattering from charged dislocations in semiconductors. The results are compared to the respective relaxation times…

Materials Science · Physics 2009-11-07 D. Jena , U. K. Mishra

The mean square atomic displacement in hcp-phase solid He-4 has been measured in crystals with a molar volume of 21.3 cm^3. It is temperature independent from 1 K to 140 mK, with no evidence for an anomaly in the vicinity of the proposed…

Other Condensed Matter · Physics 2007-08-01 E. Blackburn , J. M. Goodkind , S. K. Sinha , J. Hudis , C. Broholm , J. van Duijn , C. D. Frost , O. Kirichek , R. B. E. Down

A novel analysis of homogeneous nucleation of dislocations in sheared two-dimensional crystals described by periodized discrete elasticity models is presented. When the crystal is sheared beyond a critical strain $F=F_{c}$, the strained…

Materials Science · Physics 2008-05-09 I. Plans , A. Carpio , L. L. Bonilla

A model based on dislocation glide controlled by the nucleation and propagation of kink pairs in a high Peierls stress crystal is revisited and modified to account for changes in dislocation densities and segment lengths with temperature…

We reported a new result of the neutral impurity scattering of holes that has impact on the charge drift mobility in high purity p-type germanium crystals at 77 Kelvin. The charge carrier concentration, mobility and resistivity are measured…

Instrumentation and Detectors · Physics 2017-02-01 H. Mei , D. -M. Mei , G. -J. Wang , G. Yang

The atomic displacements associated with the freezing of metals and salts are calculated by treating crystal growth as an assignment problem through the use of an optimal transport algorithm. Converting these displacements into time scales…

Materials Science · Physics 2022-06-08 Gang Sun , Alexander Hawken , Peter Harrowell

We study the notion of superfluid critical velocity in one spatial dimension. It is shown that for heavy impurities with mass $M$ exceeding a critical mass $M_\mathrm{c}$, the dispersion develops periodic metastable branches resulting in…

Quantum Gases · Physics 2012-05-15 Michael Schecter , Alex Kamenev , Dimitri Gangardt , Austen Lamacraft

The dynamics of a crack propagating in an elastic inhomogeneous material is investigated. The variations of the average crack velocity with the external loading are measured for a brittle rock and are shown to display two distinct regimes:…

Statistical Mechanics · Physics 2008-12-18 Laurent Ponson

Crystal plasticity of sub-micron finite volumes is characterized by the flow of emergent dislocation defects, giving rise to size effects in mechanical properties and avalanche phenomena. In this chapter, we present a minimal model for…

Materials Science · Physics 2019-08-09 Stefanos Papanikolaou , Michail Tzimas

The interaction of two screw dislocations in smectic-A liquid crystals is treated using an anharmonic correction to the elastic energy density. In the present contribution the elastic energy and the force between two screw dislocations is…

Soft Condensed Matter · Physics 2020-09-02 Lubor Lejcek

We study the thermally driven spin state transition in a two-orbital Hubbard model with crystal field splitting, which provides a minimal description of the physics of LaCoO3. We employ the dynamical mean-field theory with quantum…

Strongly Correlated Electrons · Physics 2011-06-23 Jan Kunes , Vlastimil Krapek

We consider the roughening of small angle grain boundaries consisting of arrays of dislocations and found two transitions, corresponding to fluctuations of the dislocations along and perpendicular to the boundaries. The latter contributes…

Other Condensed Matter · Physics 2015-05-13 S. T. Chui

We present a new study of the nonlinear transport of a two-dimensional electron crystal on the surface of liquid helium confined in a 10 micrometer-wide channel in which the effective length of the crystal can be varied from 10 to 215…

Mesoscale and Nanoscale Physics · Physics 2018-12-03 J. -Y. Lin , A. V. Smorodin , A. O. Badrutdinov , D. Konstantinov

The mobility of surface electrons localized over helium films underlying solid substrates has been evaluated by solving the Boltzmann equation in the time relaxation approximation and the force balance equation in which an effective…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Debora Coimbra , Sviatoslav S. Sokolov , J. -P. Rino , Nelson Studart

Stressed dislocation pattern formation in crystal plasticity at finite deformation is demonstrated for the first time. Size effects are also demonstrated within the same mathematical model. The model involves two extra material parameters…

Materials Science · Physics 2018-12-04 Rajat Arora , Amit Acharya

We suggest that below a certain temperature T_k, the free energy for the creation of kinks-antikinks pairs in the dislocation network of solid He4 becomes negative. The underlying physical mechanism is the related liberation of vacancies…

Statistical Mechanics · Physics 2009-11-13 Jean-Philippe Bouchaud , Giulio Biroli

The kinetics of HCP-BCC structure phase transition is studied by precise pressure measurement technique in 4He crystals of different quality. An anomalous pressure behavior in bad quality crystals under constant volume conditions is…

Quantum Physics · Physics 2009-11-13 Nikolay Mikhin , Andrey Polev , Eduard Rudavskii , Yegor Vekhov

Compared to cubic metals, whose primary slip mode includes twelve equivalent systems, the lower crystalline symmetry of hexagonal close-packed metals results in a reduced number of equivalent primary slips and anisotropy in plasticity,…

Materials Science · Physics 2016-06-15 Mitsuhiro Itakura , Hideo Kaburaki , Masatake Yamaguchi , Tomohito Tsuru

We investigate the depinning transition occurring in dislocation assemblies. In particular, we consider the cases of regularly spaced pileups and low angle grain boundaries interacting with a disordered stress landscape provided by solute…

Statistical Mechanics · Physics 2009-11-10 Paolo Moretti , M. -Carmen Miguel , Michael Zaiser , Stefano Zapperi

Fines migration behavior can either promote or obstruct fluid flow within the reservoir and is crucial for productivity optimization that needs fundamental understanding. The present work focuses on the contributions from effective stress…