抄録
When an electron is accelerated by an applied field, there exists phase coherency between Bloch states which the electron goes through. We can interpret this effect as afterimage of electronic motion. Due to this effect, localized eigenstates (Landau states in magnetic fields or Stark states in electric fields) are formed from Bloch states if cyclic motion is completed. However, the phase coherence should exist even when the cyclic motion is incomplete. From this point of view, an electron should be expressed by a superposition of Bloch states even in low fields. We investigate the effect of the field-induced coherency on transport properties by using wavepackets formed as a result of the superposition. It is shown that the wavepackets can be correlated with the Green’s functions. We also show that the present theory is applicable to the Monte Carlo technique which enables a more precise investigation.
