Spin-orbit coupling and dimensionality at the heart of quantum magnetism of heavy transition metal oxides
Lead Research Organisation:
Science and Technology Facilities Council
Department Name: ISIS Pulsed Neutron & Muon Source
Abstract
This proposal is focused on the study of quantum materials with competing interactions. Measurements of the various quantum-mechanical phases provide the most direct manifestation of the underlying abstract physics, such as quantum spin liquid, topological behaviour and quantum entanglement. The in-depth experimental and theoretical investigations of emergent phenomena of the candidate quantum materials have been serving as a major theme of recent condensed matter physics research. Understanding the complex magnetic interactions in these novel quantum materials is crucial for the development of fundamental science in the form of modern theory of higher d transition metal oxides, as well as for the strong foundation of alternative pathways towards the design of new and exotic materials and functional devices, which hold true promise for future generation of technological applications. The investigations on the novel 5d Iridates and 4d rhodates reveal a burgeoning list of theoretical proposals as well as predictions of unusual states, such as Jeff half Mott-insulating state, the quantum spin liquid phase, Kitaev quantum magnetism, unconventional superconductivity, Weyl semimetals, correlated topological insulators, etc., which are indeed truly remarkable and stimulating. The physics of iridates, ruthenates and rhodates clearly warrants serious intellectual challenges both theoretically and experimentally, and hence, in this proposal we focus on design, synthesis and characterisation of the new candidate quantum materials within 4d Rh/Ru- and 5d Ir-based oxides. Quantum spin liquid (QSL) is a novel state of quantum magnetism where long range magnetic order is suppressed due to strong quantum fluctuations down to the lowest temperature. The gapless QSLs exhibit long-range quantum-entanglement and fractionalised spin excitations named as Majorana Fermions. Such fractionalised spin excitations are different from conventional magnons observed in compounds with long-range magnetic ordering. The present proposal is therefore aimed to investigate the exotic and unconventional magnetic ground states of iridates, ruthenates and rhodates within a variety of crystal structures and lattice geometries by implementing detailed experimental study (both laboratory based and state-of-art neutron, muon and x-ray synchrotron based advanced measurements) and ab-initio electronic structure calculations. These in-depth investigations will help in understanding the importance of various competing interactions, e.g. spin-orbit interaction, on-site Coulomb U, crystal field, Hund's coupling, hopping and electronic bandwidth. The nature of the extraordinary structural sensitivity of quantum materials also calls for extraordinarily high-quality single crystals and we are planning to synthesise such single crystals using UCL crystal growth lab at Harwell and investigate them using various central facilities.
Publications
Anand V
(2022)
Thermal conductivity, thermoelectric power and Mössbauer investigations on atiferromagnetic CeFe1.7Ir0.3Al10
in Journal of Magnetism and Magnetic Materials
Zhang J
(2022)
A ferrotoroidic candidate with well-separated spin chains
Zhang J
(2022)
A Ferrotoroidic Candidate with Well-Separated Spin Chains.
in Advanced materials (Deerfield Beach, Fla.)
Ritter C
(2022)
Magnetic structures of the iridium-based double perovskites Pr 2 NiIrO 6 and Nd 2 NiIrO 6 reinvestigated using neutron diffraction
in Physical Review Materials
Bhattacharyya A
(2022)
Multigap superconductivity in the filled-skutterudite compound LaRu 4 As 12 probed by muon spin rotation
in Physical Review B
Gutmann MJ
(2022)
New Insights on the Electronic-Structural Interplay in LaPdSb and CePdSb Intermetallic Compounds.
in Materials (Basel, Switzerland)
Bhattacharyya A
(2022)
Nodeless time-reversal symmetry breaking in the centrosymmetric superconductor Sc 5 Co 4 Si 10 probed by muon-spin spectroscopy
in Physical Review Materials
Sharma S
(2022)
Magnetic structure of the double perovskite La 2 NiIrO 6 investigated using neutron diffraction
in Physical Review Materials
Amorese A
(2022)
Metamagnetism and crystal-field splitting in pseudohexagonal CeRh 3 Si 2
in Physical Review B
Tripathi R
(2022)
Effect of 3p- and 5d-electron doping on the Kondo Semiconductor CeFe 2 Al 10
in Journal of Physics: Conference Series
Vibhakar A
(2023)
Competing charge and magnetic order in the candidate centrosymmetric skyrmion host EuGa 2 Al 2
in Physical Review B
He Z
(2023)
Spin fluctuations in Sr 1.8 La 0.2 RuO 4
in Physical Review B
Bhattacharyya A
(2023)
Superconducting Gap Structure of Filled Skutterudite LaOs4As12 Compound through µSR Investigations
in Magnetochemistry
Tripathi R
(2023)
Effect of Co-Doping on the Magnetic Ground State of the Heavy-Fermion System CeCu2Ge2 Studied by Neutron Diffraction
in Magnetochemistry
Anand V
(2023)
Role of crystal-field ground state in the classical spin-liquid behavior of the quasi-one-dimensional spin-chain system Sr 3 NiPtO 6
in Physical Review B
Das D
(2023)
Superconducting Gap Structure of the Noncentrosymmetric Topological Superconductor Candidate HfRuP
in Magnetochemistry
Bhattacharyya A
(2023)
µSR Study of Unconventional Pairing Symmetry in the Quasi-1D Na2Cr3As3 Superconductor
in Magnetochemistry
Tripathi R
(2023)
Quantum Griffiths singularity in the stoichiometric heavy-fermion system CeRh 4 Al 15
in Physical Review B
Roman M
(2023)
Charge density wave and crystalline electric field effects in TmNiC 2
in Physical Review B
Description | Muon spin rotation study on Iridates La3Ir3O11 |
Organisation | Tohoku University |
Country | Japan |
Sector | Academic/University |
PI Contribution | I have started collaboration with Prof. AOYAMA on investigating role of spin-orbital coupling in iridates. He has provided La3Ir3O11 materials and we will submit muon spin rotation and neutron scattering proposals at ISIS Facility, ILL, J-PARC and PSI. His details are given below. Prof. Takuya AOYAMA Department of Physics, Tohoku University 6-3 Aramaki-Aoba, Aobaku, Sendai, Miyagi 980-8578, JAPAN Phone:+81-22-795-6488, Mail:aoyama@tohoku.ac.jp |
Collaborator Contribution | Provided samples. |
Impact | At present we are planning for beam time proposals, which will results in future publications. |
Start Year | 2022 |