Sequential and co-tunneling behavior in the temperature-dependent   thermopower of few-electron quantum dots
  We have studied the temperature dependent thermopower of gate-defined, lateral quantum dots in the Coulomb blockade regime using an electron heating technique. The line shape of the thermopower oscillations depends strongly on the contributing tunneling processes. Between 1.5 K and 40 mK a crossover from a pure sawtooth- to an intermitted sawtooth-like line shape is observed. The latter is attributed to the increasing dominance of cotunneling processes in the Coulomb blockade regime at low temperatures. 
R. Scheibner (1), E.G. Novik (1), T. Borzenko (1), M. Koenig (1), D.   Reuter (2), A.D. Wieck (2), H. Buhmann (1), L.W. Mole...