Abstract
Directly contradictory arguments coexist regarding the conservation rule of orbital angular momentum in spontaneous parametric down-conversion. We analytically show how this rule is decided by spatial symmetry. We discover that the down-converted photon pairs can carry non-negligible extrinsic orbital angular momentum in the degrees of relative-movement freedom due to spatial symmetry breaking, leading to nonconservation of total orbital angular momentum in type-II down-conversion. Also, we demonstrate that the traditional technique does not measure the extrinsic orbital angular momentum.
| Original language | English (US) |
|---|---|
| Article number | 163602 |
| Journal | Physical review letters |
| Volume | 101 |
| Issue number | 16 |
| DOIs | |
| State | Published - Oct 17 2008 |
ASJC Scopus subject areas
- General Physics and Astronomy