Quantum transport in ballistic quantum dots

Carriers in small 3D quantum boxes take us from unintentional quantum dots in MOSFETs (arising from the doping fluctuations) to single-electron quantum dots in semiconductor heterostructures. In between these two extremes are the realm of open, ballistic quantum dots, in which the transport can be quite regular. Several issues must be considered in treating the transport in these dots, among which are: (1) phase coherence within the dot; (2) the transition between semi-classical and fully quantum transport, (3) the role of the contacts, vis-à-vis the fabricated boundaries, and (4) the actual versus internal boundaries. In this paper, we discuss these issues, including the primary observables in experiment, the intrinsic nature of oscillatory behavior in magnetic field and dot size, and the connection to semi-classical transport emphasizing the importance of the filtering by the input (and output) quantum point contacts.