Operator with large spin and spinning D3-brane

We consider the conformal dimension of an operator with large spin, using a spinning D3-brane with electric flux in AdS5 x S5 instead of spinning fundamental string. This spinning D3-brane solution seems to correspond to an operator made by taking trace in a large symmetric representation. The conformal dimension, the spin and the R-charge show a scaling relation in a certain region of parameters. In the small string charge limit, the result is consistent with the fundamental string picture. There is a phase transition when the fundamental string charge become larger than a certain critical value; there is no stable D3-brane solution above the critical value.