  We fabricated a gated-vertical (In,Ga)As quantum dot with an Al2O3 gate
insulator deposited using atomic layer deposition and investigated its
electrical transport properties at low temperatures. The gate voltage
dependence of the dI/dV-V characteristics shows clear Coulomb diamonds at 1.1K.
The metal-insulator gate structure allowed us to control the number of
electrons in the quantum dot from 0 to a large number estimated to be about
130.
