Table 1 The trace of each subspace ρ before and after the filter.

This provides the probability to project onto a particular subspace spanned by the states with OAM values ±ℓ.

SubspaceTr[ρ] before the filterTr[ρ] after the filter
ρ10.370 ± 0.0020.556 ± 0.001
ρ20.319 ± 0.0020.018 ± 0.001
ρ30.278 ± 0.0020.409 ± 0.001