An Efficient Tomographic Scheme for a Single-Particle Multi-mode System

Abstract

An experimental tomographic scheme to measure the density matrix of a quantum state of a single-particle multi-mode system is proposed. The scheme requires only single qudit rotations and straightforward projection measurements. The number of the projection measurements required to complete the experiment scales linearly with the dimension of the system. The proposed scheme can be used to determine the purity of the state and to estimate the degree of entanglement between the system being measured and its surroundings.