NON-MARKOVIAN BEHAVIOR OF QUANTUM-CONFINED ELECTRONIC SYSTEMS

The holomorphic memory function method is modified to include geometri cal confinement. A 'ballistic memory function' is identified, showing that energy quantization due to lateral confinement is associated with a retardation in the system. Consequently, the ballistic conductance quantization of waveguides is shown to be caused by long-lived correla tions between values of the applied field at different points in the d evice. A renormalized force correlation function shows the mutual infl uence of geometrical confinement and scattering mechanisms: confinemen t-induced memory effects modify the elastic scattering white relaxatio n spectrum and transform it into a scattering mechanism with enhanced retardation properties. Evidence of these phenomena is given through t he numerical evaluation of the ac conductance and time-dependent curre nt for a rectangular cross-section wire of finite length.