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Formación de patrones en los semiconductores
V V Bel'kov1, J Hirschinger1, V Novák2
1Institut für Experimentelle und Angewandte Physik, Universität Regensburg, 93040 Regensburg, Germany.
Nature
|April 19, 2018
Resumen
Las propiedades no lineales de los semiconductores conducen a transiciones de fase de no equilibrio. A bajas temperaturas, la ionización por impacto provoca un aumento abrupto de la densidad del portador libre, formando patrones de corriente filamentaria.
Área de la Ciencia:
- Física de los semiconductores
- Física de la materia condensada
Sus antecedentes:
- La dinámica y el transporte del portador no lineal son cruciales en los semiconductores.
- La generación autocatalítica de portadores libres a través de la ionización por impacto es una no linealidad clave a baja temperatura.
Objetivo del estudio:
- Investigar las transiciones de fase de no equilibrio en semiconductores impulsados por procesos no lineales.
- Comprender el papel de la ionización de impacto en la generación y el transporte de portadores.
Principales métodos:
- Análisis de los procesos de generación y recombinación no lineales.
- Estudio de los mecanismos de transporte de carga no lineal.
- Investigación de los efectos del campo eléctrico en la densidad de la portadora.
Principales resultados:
- Las no linealidades pueden inducir transiciones de fase de no equilibrio en semiconductores.
- La ionización de impacto a bajas temperaturas conduce a un aumento abrupto de la densidad del portador libre en un campo eléctrico crítico.
- Los campos eléctricos estáticos dan lugar a patrones de corriente filamentaria complejos localizados en los contactos.
Conclusiones:
- El comportamiento del semiconductor no lineal puede conducir a transiciones de fase únicas.
- La ionización por impacto es un mecanismo fundamental para la generación de portadores y el transporte no lineal.
- Los patrones de corriente filamentaria son un resultado característico de estas no linealidades en los campos eléctricos.
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