Teoría de la Materia Condensada y GPGPU [talk in Spanish]

Charla virtual en la Universidad San Francisco de Quito, abril 7 2021. Virtual seminar talk in Spanish.


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Depinning Olympics [paper and game!]

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A one dimensional elastic string driven by a uniform force in a random medium is a minimal model for a field driven domain wall in a large family of thin-film ferromagnetic materials.  The motion of the elastic string at zero temperature is characterized by a depinning threshold fc , such that if the driving is f<fc the string is blocked after a transient, while for f>fc it slides and never stops, acquiring a well defined and finite steady-state average velocity. At finite temperature, thermal activation allows the string to have a finite average velocity at all finite driving forces however. As a result, the mean velocity is an interesting function v(T,f) which presents a creep regime for f<fc , a depinning region for f>~fc , and a flow regime for f>>fc . The depinning transition was recently characterized experimentally by L. J. Albornoz et al. in thin-film ferrimagnets at very low temperatures. Now it is your turn to find a depinning transition! The applet ...
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