Effect of stray capacitances on single electron tunneling in a turnstile

Based on the exact solution for the potential profile of the 2N turnstile with equal junction capacitances C, equal stray capacitances C0, and a coupling capacitance Cc, we obtain explicit expressions for the Gibbs free energy as well as the corresponding charging energy and the barrier height. In particular, we analyze the effects of the stray capacitances on the turnstile operation. In the C0=0 case, our results for the turnstile operation reduce to those of D. V. Averin, A. A. Odintsov, S. V. Vyshenskii [J. Appl. Phys. 73, 1297 (1993)]. In general, when C0/C is increased, the operable region of the turnstile decreases. Thus, in order to have a high quality turnstile, it is necessary to keep the stray capacitances small.