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arXiv · 2408.11163

Tomonaga-Luttinger liquid and quantum criticality in spin-1/2 antiferromagnetic Heisenberg chain C14H18CuN4O10 via Wilson ratio

Sharath Kumar Channarayappa·Sankalp Kumar·N. S. Vidhyadhiraja·Sumiran Pujari·M. P. Saravanan·Amal Sebastian·Eun Sang Choi·Shalinee Chikara·Dolly Nambi·Athira Suresh·Siddhartha Lal·D. Jaiswal-Nagar
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Abstract

The ground state of a one-dimensional spin-1/2 uniform antiferromagnetic Heisenberg chain (AfHc) is a Tomonaga-Luttinger liquid which is quantum-critical with respect to applied magnetic fields upto a saturation field Hs beyond which it transforms to a fully polarised state. Wilson ratio has been predicted to be a good indicator for demarcating these phases [Phys. Rev. B 96, 220401 (2017)]. From detailed temperature and magnetic field dependent magnetisation, magnetic susceptibility and specific heat measurements in a metalorganic complex and comparisons with field theory and quantum transfer matrix method calculations, the complex was found to be a very good realisation of a spin-1/2 AfHc. Wilson ratio obtained from experimentally obtained magnetic susceptibility and magnetic contribution of specific heat values was used to map the magnetic phase diagram of the uniform spin-1/2 AfHc over large regions of phase space demarcating Tomonaga-Luttinger liquid, saturation field quantum critical, and fully polarised states. Luttinger parameter and spinon velocity were found to match very well with the values predicted from conformal field theory.

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Sharath Kumar Channarayappa, Sankalp Kumar, N. S. Vidhyadhiraja, Sumiran Pujari, M. P. Saravanan, Amal Sebastian, Eun Sang Choi, Shalinee Chikara, Dolly Nambi, Athira Suresh, Siddhartha Lal, D. Jaiswal-Nagar. 2024-08-20. Tomonaga-Luttinger liquid and quantum criticality in spin-1/2 antiferromagnetic Heisenberg chain C14H18CuN4O10 via Wilson ratio. https://doi.org/10.1093/pnasnexus%2Fpgae363

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