Stars of the quantum Universe: extremal constellations on the Poincare sphere
2015 (English)In: Physica Scripta, ISSN 0031-8949, E-ISSN 1402-4896, Vol. 90, no 10, 108008Article in journal (Refereed) Published
The characterization of the polarization properties of a quantum state requires the knowledge of the joint probability distribution of the Stokes variables. This amounts to assessing all the moments of these variables, which are aptly encoded in a multipole expansion of the density matrix. The cumulative distribution of these multipoles encapsulates in a handy manner the polarization content of the state. We work out the extremal states for that distribution, finding that SU(2) coherent states are maximal to any order, so they are the most polarized allowed by quantum theory. The converse case of pure states minimizing that distribution, which can be seen as the most quantum ones, is investigated for a diverse range of number of photons. Exploiting the Majorana representation, the problem appears to be closely related to distributing a number of points uniformly over the surface of the Poincare sphere.
Place, publisher, year, edition, pages
[Bjork, Gunnar] Royal Inst Technol KTH, Dept Appl Phys, AlbaNova Univ Ctr, SE-10691 Stockholm, Sweden. [Grassl, Markus; Leuchs, Gerd; Sanchez-Soto, Luis L.] Max Planck Inst Phys Lichts, D-91058 Erlangen, Germany. [Grassl, Markus; Leuchs, Gerd; Sanchez-Soto, Luis L.] Univ Erlangen Nurnberg, Inst Opt Informat & Photon, D-91058 Erlangen, Germany. [de la Hoz, Pablo; Sanchez-Soto, Luis L.] Univ Complutense, Fac Fis, Dept Opt, E-28040 Madrid, Spain., 2015. Vol. 90, no 10, 108008
polarization, quantum optics, fluctuations, anti-coherence, Majorana representation, spherical t-design
IdentifiersURN: urn:nbn:se:kth:diva-176356DOI: 10.1088/0031-8949/90/10/108008ISI: 000362529800018ScopusID: 2-s2.0-84945232236OAI: oai:DiVA.org:kth-176356DiVA: diva2:867053
QC 201511042015-11-042015-11-032015-11-04Bibliographically approved