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Haldane topological spin-1 chains in a planar metal-organic framework
Pagnareach Tin1, Michael J Jenkins1, Jie Xing2
1Department of Chemistry, University of Tennessee, Knoxville, TN, 37996, USA.
Nature Communications
|September 6, 2023
Summary
Researchers discovered a rare two-dimensional metal-organic framework (MOF) exhibiting Haldane topological properties. This material, NiBO, features antiferromagnetic chains with potential applications in spintronics and quantum computing.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Information Science
Background:
- Haldane topological materials possess unique antiferromagnetic chains with symmetry-protected energy gaps.
- These materials are promising for spintronics and quantum computing applications.
- Typically, Haldane topological solids are 3D crystal structures containing spin-1 chains.
Purpose of the Study:
- To investigate the material [Ni(μ-4,4'-bipyridine)(μ-oxalate)]n (NiBO) for Haldane topological properties.
- To characterize the structure and magnetic behavior of NiBO.
- To explore the potential of 2D metal-organic frameworks (MOFs) as Haldane topological materials.
Main Methods:
- Single-crystal X-ray diffraction and variable-temperature powder neutron diffraction (VT-PND) for structural analysis.
- Variable-temperature inelastic neutron scattering (VT-INS), DC susceptibility, specific heat, and high-field electron spin resonance for magnetic characterization.
- Unbiased quantum Monte Carlo simulations and density-functional theory (DFT) calculations for theoretical validation and phonon property analysis.
Main Results:
- NiBO adopts a 2D metal-organic framework (MOF) structure with Ni2+ spin-1 chains.
- The material exhibits Haldane topological properties, characterized by a gap between singlet and triplet states.
- Experimental and computational results confirm the absence of significant spin-phonon coupling.
Conclusions:
- NiBO is identified as a rare two-dimensional (2D) MOF exhibiting Haldane topological properties.
- The findings expand the scope of materials for spintronics and quantum computing.
- This work highlights the potential of MOFs in realizing novel topological quantum phenomena.
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