Magnetic quantum criticality in quasi‐one‐dimensional Heisenberg antiferromagnet |
| |
| Authors: | V R Shaginyan V A Stephanovich K G Popov E V Kirichenko S A Artamonov |
| |
| Affiliation: | 1. Petersburg Nuclear Physics Institute, NRC Kurchatov Institute, Gatchina, Russia;2. Clark Atlanta University, Atlanta, USA;3. Institute of Physics, Opole University, Opole, Poland;4. Komi Science Center, Ural Division, RAS, Syktyvkar, Russia;5. Institute of Mathematics and Informatics, Opole University, Opole, Poland |
| |
| Abstract: | 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  (temperature—magnetic field) phase diagram, that contains Landau‐Fermi‐liquid, crossover and non‐Fermi liquid parts, thus resembling that of heavy‐fermion compounds. |
| |
| Keywords: | quasi‐one‐dimensional systems spin chain models non‐fermi‐liquid ground states strongly correlated electron systems heavy fermions |
|
|
