Generalized partial measurements

Abstract

We introduce a type of measurements that generalize the so-called "partial measurements" performed in recent years with phase qubits. While in the case of partial measurements it has been demonstrated that one could undo the effect of the measurement only for non-switching events, we show here that generalized partial measurements can be reversed probabilistically for both switching and non-switching events. We calculate the associated Fisher information and discuss the estimation sensitivity for quantum tomography. Two ways of implementing this type of measurements with superconducting qubits are proposed.