Projective Quantum State Tomography
RAUL AMAURY ROBLES1*, Ray-Kuang Lee1,2
1Institute of Photonic Technologies, National Tsing Hua University, Hsinchu, Taiwan
2Department of Physics, National Tsing Hua University, Hsinchu,, Taiwan
We derive the expressions for the Wigner function and its corresponding quadrature measurements for an arbitrary state in terms of the density matrix coefficients. With the help of discrete Fourier transform, we illustrate an alternative formulation for quantum state tomography obtained directly from experimental data, by projecting experimental quadrature measurements of a quantum state into an appropriate basis without the angle dependence. As our methodology converts the problem into a set of linear systems, the prior knowledge of the quantum state is not required both for mixed or pure states. The maximum photon resolution is only dependent on the number of quadrature measurements.

Keywords: Quantum State Tomography, Wigner Function, Tomography