Coulomb Blockade Oscillations in the Thermopower of Open Quantum Dots

We consider Coulomb blockade oscillations of thermoelectric coefficients of a single electron transistor based on a quantum dot strongly coupled to one of the leads. An analytic expression for the thermopower as a function of temperature T and the reflection amplitude r in the quantum point contact is obtained. Two regimes can be identified: T<<EC/r/2 and T>>EC/r/2, where EC is the charging energy of the dot. The former regime is characterized by a weak logarithmic dependence of the thermopower on the reflection coefficient, in the latter the thermopower is linear in the reflection coefficient /r/2 but depends on temperature only logarithmically.