2013/10/31 by Valentina Bisogni, Krzysztof Wohlfeld, Satoshi Nishimoto +16 · 1 citation
Physics and Astronomy · #Advanced Condensed Matter Physics #Anisotropy #Antiferromagnetism #Charge (physics) #Computer science #Condensed matter physics #Curse of dimensionality #Electron #Fractionalization #Machine learning #Magnetic properties of thin films #Physics #Physics of Superconductivity and Magnetism #Quantum mechanics #Quasiparticle #Spin (aerodynamics) #Spinon #Strongly correlated material #cond-mat.str-el
paper · pdf · doi:10.1103/physrevlett.114.096402
published as Physical Review Letters 114, 096402 (2015) · 6 pages, 4 figure
openalex publication_date 2015/03/04 · arxiv created 2015/03/05 · arxiv updated 2015/03/06 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/06
Fractionalization of an electronic quasiparticle into spin, charge, and orbital parts is a fundamental and characteristic property of interacting electrons in one dimension. However, real materials are never strictly one dimensional and the fractionalization phenomena are hard to observe. Here we studied the spin and orbital excitations of the anisotropic ladder material CaCu2O3, whose electronic structure is not one dimensional. Combining high-resolution resonant inelastic x-ray scattering experiments with theoretical model calculations, we show that (i) spin-orbital fractionalization occurs in CaCu2O3 along the leg direction x through the xz orbital channel as in a 1D system, and (ii) no fractionalization is observed for the xy orbital, which extends in both leg and rung direction, contrary to a 1D system. We conclude that the directional character of the orbital hopping can select different degrees of dimensionality. Using additional model calculations, we show that spin-orbital separation is generally far more robust than the spin-charge separation. This is not only due to the already mentioned selection realized by the orbital hopping, but also due to the fact that spinons are faster than the orbitons.