Lw. Molenkamp et M. Kemerink, STOCHASTIC COULOMB-BLOCKADE AND SCALING OF CHARGING ENERGY IN A DOUBLE-QUANTUM DOT SYSTEM, Superlattices and microstructures, 16(3), 1994, pp. 275-278
We have studied the transport properties of a device consisting of two
quantum dots, defined electrostatically in a (Al,Ga)As heterostructur
e. In the series conductance of the two dots, we observe irregularly s
paced conductance peaks of fluctuating amplitude. This behaviour resul
ts from transport in the stochastic Coulomb blockade regime. In a seco
nd experiment, we measure the charging energy of one dot through the e
ffect of its potential (which varies in a saw-tooth fashion with gate
voltage) on the conductance of the other dot. We find that the chargin
g energy scales quadratically with the reflection probability of the t
unnel barriers, in agreement with a recent theory.