Traversal times and charge confinement for spatially dependent effective masses within semiconductor heterostructures: the quantum potential approach

The classical traversal time is a well-defined functional of the carrier trajectory and in graded heterostructures acquires significant corrections due to the position-dependent effective mass. The quantum potential corrections for pure states and the corrections to quantum Monte Carlo for mixed states are derived using the Wigner formalism. Application to graded SiGe shows additional transport corrections, including enhanced charge confinement, which are of the same order as the conventional constant mass density gradient corrections. (C) 2002 Elsevier Science B.V. All rights reserved.