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Updated: Feb 11, 2026

Understanding Cerebellar Pattern Formation
Published on: November 1, 2007
Pattern formation in semiconductors
V V Bel'kov1, J Hirschinger1, V Novák2
1Institut für Experimentelle und Angewandte Physik, Universität Regensburg, 93040 Regensburg, Germany.
Abstract:
In semiconductors, nonlinear generation and recombination processes of free carriers and nonlinear charge transport can give rise to non-equilibrium phase transitions, . At low temperatures, the basic nonlinearity is due to the autocatalytic generation of free carriers by impact ionization of shallow impurities. The electric field accelerates free electrons, causing an abrupt increase in free carrier density at a critical electric field. In static electric fields, this nonlinearity is known to yield complex filamentary current patterns bound to electric contacts.
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