Introduction: Basics of High Field Transport

Abstract

In this chapter, we first briefly discuss high-field transport in solids and introduce some of the key phenomena. Then, we provide a discussion of standard drift transport versus ballistic or coherent transport, the latter being typical in the case of Bloch oscillations. The key point is that the wave-like quantum-mechanical nature of the electrons becomes important when they reach the upper edge of the band. Instead of linear drift transport along the electric field direction, one obtains oscillations around a fixed point in space. These spatially localized oscillations compete with the effect of Zener tunneling, where the coupling to higher bands leads again to transport in the electric field direction.