Artículos de revistas
Anomalous dephasing scattering rate of two-dimensional electrons in double quantum well structures
Fecha
2008Registro en:
PHYSICAL REVIEW B, v.78, n.11, 2008
1098-0121
10.1103/PhysRevB.78.115311
Autor
Pagnossin, Ivan Ramos
MEIKAP, A. K.
Lamas, Tomás Erikson
Gusev, Gennady
PORTAL, J. C.
Institución
Resumen
The results on the measurement of electrical conductivity and magnetoconductivity of a GaAs double quantum well between 0.5 and 1.1 K are reported. The zero magnetic-field conductivity is well described from the point of view of contributions made by both the weak localization and electron-electron interaction. At low field and low temperature, the magnetoconductivity is dominated by the weak localization effect only. Using the weak localization method, we have determined the electron dephasing times tau(phi) and tunneling times tau(t). Concerning tunneling, we concluded that tau(t) presents a minimum around the balance point; concerning dephasing, we observed an anomalous dependence on temperature and conductivity (or elastic mean free path) of tau(phi). This anomalous behavior cannot be explained in terms of the prevailing concepts for the electron-electron interaction in high-mobility two-dimensional electron systems.