This document describes research into using a circular nanoslit to convert spin angular momentum to orbital angular momentum. Experiments showed that a circularly polarized input beam was converted to an elliptically polarized output with opposite handedness and a phase difference between components. This demonstrated that the nanoslit acts as a space-variant quarter-wave plate, effectively coupling spin and orbital angular momentum while conserving total angular momentum. The researchers constructed and analyzed a novel spin-to-orbit angular momentum coupling device.
3. Slit in a metal film
Chimento, Kuzmin, Bosman, et al. (2011). Opt. Expr. 19 (24), 24219.
4. Slit in a metal film
Subwavelength “Infinite” in the other
in one direction
Chimento, Kuzmin, Bosman, et al. (2011). Opt. Expr. 19 (24), 24219.
5. Almost ideal metal
TM
TE
Slit width in λ
Chimento, Kuzmin, Bosman, et al. (2011). Opt. Expr. 19 (24), 24219.
6. Real metal
TM
TE
Slit width in λ
Chimento, Kuzmin, Bosman, et al. (2011). Opt. Expr. 19 (24), 24219.
7. Real metal
Input state Analyzer rotation
Measured output
If designed carefully,
there is a point where the
slit is a quarter-wave plate
Chimento, Kuzmin, Bosman, et al. (2011). Opt. Expr. 19 (24), 24219.
8. We roll the slit up
into a circle
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