PIRSA:21110022

Tuning multipolar orders and critical points in d-orbital Mott insulators

Paramekanti, A. (2021). Tuning multipolar orders and critical points in d-orbital Mott insulators. Perimeter Institute. https://pirsa.org/21110022

Paramekanti, Arun. Tuning multipolar orders and critical points in d-orbital Mott insulators. Perimeter Institute, Nov. 22, 2021, https://pirsa.org/21110022 

          @misc{ pirsa_PIRSA:21110022,
            doi = {10.48660/21110022},
            url = {https://pirsa.org/21110022},
            author = {Paramekanti, Arun},
            keywords = {Condensed Matter},
            language = {en},
            title = {Tuning multipolar orders and critical points in d-orbital Mott insulators},
            publisher = {Perimeter Institute},
            year = {2021},
            month = {nov},
            note = {PIRSA:21110022 see, \url{https://pirsa.org}}
          }

Arun Paramekanti

University of Toronto

Talk number
PIRSA:21110022
Collection
Talk Type
Subject
Abstract

Traditionally, magnetism in solids deals with ordering patterns of the electron magnetic dipole moment, as probed, for instance, via neutron diffraction. However, f-electron heavy fermion systems are well-known candidates for more complex forms of symmetry breaking, involving higher-order magnetic or electric multipoles. In this talk, I will discuss our recent theoretical proposal for Ising octupolar order in d-orbital systems, which appears to explain a wide range of experiments in certain 5d transition metal oxides with spin-orbit coupling. The proposed Ising ferro-octupolar order is shown to be linked to a type of orbital loop-current order. Deviations from cubic symmetry, via strain or surfaces, induces a transverse field on the octupolar order which can lead to surface quantum phase transitions, or transitions in thin films or in strained 3D crystals. We propose further experimental tests of our proposal.