Ultrabroadband, ultranarrowband and ultrapassband composite polarisation half-wave plates, ultrabroadband composite polarisation pi-rotators and on the quantum-classical analogy

TL;DR

This paper introduces composite polarization devices that achieve ultrabroadband, ultranarrowband, and ultrapassband rotations and filters, with applications in quantum and classical polarization control, demonstrating robustness and versatility.

Contribution

It presents novel composite pulse designs for polarization control, unifying classical and quantum analogies, and demonstrating their effectiveness in various regimes.

Findings

Achromatic and chromatic polarization devices with ultrabroadband capabilities.

Quantum control of X and Z gates with enhanced robustness.

Unified classical-quantum polarization control methods.

Abstract

Composite pulses, which produce ultrabroadband, ultranarrowband and ultrapassband $x$-, $y$-) rotations by $\theta = \pi$ on the Bloch-Poincar\'e sphere, are presented. The first class plays a role for design of achromatic polarisation retarders, when the second class corresponds to chromatic polarisation filters. The third class is an assortment of the above two classes. Besides, composite pulses, which produce ultrabroadband $z$-) rotations by $\zeta = \pi$ on the same sphere, are presented. These phasal pulses coincide with achromatic polarisation $\pi$ rotators. On the quantum-classical analogy, we obtain ultrarobust, ultrasensitive and ultrasquare quantum control of a $X$ gate and ultrarobust quantum control of a $Z$ gate.