## Chapter 3

Quantum Ballistic Transport

Under the condition that the size of a device structure is comparable to the De Broglie wavelength of
the electron, the transport properties of the device are described by the laws of quantum mechanics.
The quantum ballistic regime is valid if the dimension of the structure is reduced below the mean free
path of the electron [37]. The basic equations of quantum ballistic device simulations, namely the
Poisson equation and the Schrödinger equation, are discussed in this section. Furthermore, we give
attention to issues regarding boundary value problems that arise in semiconductor transport
theory.