6533b827fe1ef96bd12872c4

RESEARCH PRODUCT

Magnetic quantum criticality in quasi-one-dimensional Heisenberg antiferromagnet Cu(C4H4N2)(NO3)2

subject

non-fermi-liquid ground statesstrongly correlated electron systemsquasi-one-dimensional systemheavy fermionsspin chain models

description

We analyze exciting recent measurements [Phys. Rev. Lett. 114 (2015) 037202] of the magnetization, differential susceptibility and specific heat on one dimensional Heisenberg antiferromagnet Cu(C4H4N2)(NO3)2 (CuPzN) subjected to strong magnetic fields. Using the mapping between magnons (bosons) in CuPzN and fermions, we demonstrate that magnetic field tunes the insulator towards quantum critical point related to so-called fermion condensation quantum phase transition (FCQPT) at which the resulting fermion effective mass diverges kinematically. We show that the FCQPT concept permits to reveal the scaling behavior of thermodynamic characteristics, describe the experimental results quantitatively, and derive for the first time the inline image (temperature—magnetic field) phase diagram, that contains Landau-Fermi-liquid, crossover and non-Fermi liquid parts, thus resembling that of heavy-fermion compounds.

10.1002/andp.201500352https://doi.org/10.1002/andp.201500352