Sub‐Planck structures and Quantum Metrology

Abstract

The significance of sub‐Planck structures in relation to quantum metrology is explored, in close contact with experimental setups. It is shown that an entangled cat state can enhance the accuracy of parameter estimations. The possibilty of generating this state, in dissipative systems has also been demonstrated. Thereafter, the quantum Cramer‐Rao bound for phase estimation through a pair coherent state is calculated, which achieves the maximum possible resolution in an interferometer.