Saturation of phase breaking in an open ballistic quantum dot

One of the key parameters for the observation of quantum interference effec ts in mesoscopic systems is the phase-breaking time tau(phi). While there h ave been many measurements of this important phase-breaking time in diffusi ve mesoscopic structures, there have been relatively few studies of phase b reaking in zero-dimensional structures. Here, a saturation of the phase-bre aking time at low temperatures is found, with a decay at higher temperature s generally of the form of T-2/3. Variation with dot size suggests a scalin g in which the phase-breaking interaction is described by the total number of electrons N = nA within the dot. (C) 1999 Elsevier Science B.V. All righ ts reserved.