Resumo

SANJINES C., Diego. A LATTICE EFFECT PRODUCED DURING THE FREE PROPAGATION OF A BLOCH ELECTRON. Revista Boliviana de Física [online]. 2009, vol.15, n.15, pp.1-8. ISSN 1562-3823.

A study is carried out of an effect due to the structure of the lattice in the propagation of a one-dimensional Bloch electron. The dynamics of this propagation in the presence of certain external potentials are well known: the Bloch oscillation in the presence of a lineal potential and the dynamic localization in the presence of harmonic potentials. In the absence of an external potential (free propagation), both the semi classic theory and the quantum theory predict a constant propagation velocity which is verified by numerical simulations of the Schrdinger equation. In this case, the Gaussian wavepacket that simulates the electron in its initial state, evolves itself into an asymmetrical gaussian maintaining the centre of mass at a constant velocity. However the wavepackets peak propagates with greater velocity, indicating that the center of mass lags behind the effective center of the electrical interaction. We propose an experimental scenario in which an interesting physical consequence of such a lag would manifest itself in an ideal 2D crystal.

Palavras-chave : electronic transport theory; conductivity phenomena; hopping transport.

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