In the original paper [1], the ellipse shape parameters $(a,\psi ,\chi )$ of a polarization state were expressed by the parameters for phase retardation $({ϵ}_1,{ϵ}^{\prime })$ and relative transmittance ($\tau$) of electro-optic modulators in Eqs. (9a)–(9c). However, there were trigonometric function errors in Eqs. (9b) and (9c). The correct expressions of the two equations should be

This correction does not affect the explanation of the theoretical framework in the main text.

In the sections for experimental results (Section 4) and discussion (Section 5), we sometimes referred to Eqs. (9a)–(9c) for the evaluation of the experimental results. We actually used the correct versions of the equations, as shown above. Thus, we do not need to modify the results and discussion.