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arXiv · 1409.3919

Experimental Evidences of Quantum Phase Transition in a Spin Cluster Compound

Tanmoy Chakraborty·Harkirat Singh·Chiranjib Mitra
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Abstract

Experimental realization of magnetic field induced quantum phase transition (QPT) is reported for NH4CuPO4.H2O, a two spin cluster material with isotropic Heisenberg interaction. Experimental magnetization and specific heat data have been collected as a function of temperature and magnetic field. Experimental data have been analyzed in terms of Heisenberg dimer model. Two quantum complementary observables representing local and non-local properties of the spins are constructed using the experimental data and a clear evidence of QPT is observed through partial quantum information sharing when the magnetic field is swept through a particular value. Signature of QPT is also observed when specific heat is measured as a function of magnetic field at low temperature. Furthermore, using the experimental specific heat data, magnetic energy values are calculated and their variations are captured as a function of magnetic field and temperature.

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Tanmoy Chakraborty, Harkirat Singh, Chiranjib Mitra. 2014-09-13. Experimental Evidences of Quantum Phase Transition in a Spin Cluster Compound. https://doi.org/10.1016/j.jmmm.2015.08.053

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