Magnetic fragmentation and quantum effects in Nd2Zr2O7

          @misc{ scivideos_PIRSA:17060042,
            doi = {10.48660/17060042},
            url = {https://pirsa.org/17060042},
            author = {Lhotel, Elsa},
            keywords = {Quantum Matter},
            language = {en},
            title = {Magnetic fragmentation and quantum effects in Nd2Zr2O7},
            publisher = {Perimeter Institute for Theoretical Physics},
            year = {2017},
            month = {jun},
            note = {PIRSA:17060042 see, \url{https://scivideos.org/index.php/pirsa/17060042}}
          }
          

Abstract

By means of neutron scattering measurements, we have observed magnetic fragmentation in the pyrochlore oxide Nd2Zr2O7, in which the Nd3+ ion has a strong Ising character and ferromagnetic interactions are inferred from the positive Curie-Weiss temperature θCW = 195 mK [2]. In this system, an “all in - all out” ordered state, with a reduced magnetic moment, coexists below TN = 285 mK with a fluctuating state [3]. Experimentally, the fragmentation manifests itself via the superposition of magnetic Bragg peaks, characteristic of the antiferromagnetic ordered phase, and a pinch point pattern, characteristic of the Coulomb phase [4]. The finite energy of the pinch point pattern and the dispersive modes that emerge from it, points out the quantum origin of the fragmentation in Nd2Zr2O7 [5], which comes from the very peculiar “dipolar-octopolar” nature of the Kramers Nd3+ doublet.