Magnetic flux induce dissipation effect on the quantum phase diagram of mesoscopic SQUID array

We present the quantum phase diagram of mesoscopic SQUID array. We predict different quan- tum phases and the phase boundaries along with several special points. We present the results of magnetic flux induced dissipation on these points and also on the phase boundaries. The Josephson couplings at these points are dependant on the system parameter in a more complicated fashion and differ from the Ambegaokar and Baratoff relation. We derive the analytical relation between the dissipation strength and Luttinger liquid parameter of the system. We observe some interesting behaviour at the half-integer magnetic flux quantum and also the importance of co-tunneling effect.