  This paper reviews several applications of photonic side-bands, used by
Buttiker and Landauer in their theory of traversal time in tunneling [Phys.
Rev. Lett. 49, 1739 (1982)], in transport and optics of mesoscopic systems.
Topics include generalizations of the transmission theory of transport to
time-dependent situations, optics and transport of mesoscopic systems in THz
electromagnetic fields, and phase-measurements of photon-assisted tunneling
through a quantum dot.
