Nonlinear magnetic susceptibility and aging phenomena in a reentrant ferromagnet: Cu0.2Co0.8Cl2-FeCl3 graphite bi-intercalation compound
Abstract
Linear and nonlinear dynamic properties of a reentrant ferromagnet Cu0.2Co0.8Cl2-FeCl3 graphite bi-intercalation compound are studied using ac and dc magnetic susceptibility. This compound undergoes successive phase transitions at the transition temperatures Th(=16 K), Tc(=9.7 K), and TRSG(=3.5 K). The static and dynamic behaviors of the reentrant spin-glass phase below TRSG are characterized by those of normal spin-glass phase with critical exponent β=0.57±0.10 and a dynamic critical exponent x=8.5±1.8. In the ferromagnetic phase (TRSG⩽T⩽Tc), a prominent nonlinear magnetic susceptibility is observed. The relaxation of the absorption χ″(ω,t) with time t exhibits a weak power-law decay: χ″(ω,t)≈t-b″ where b″≈0.07. These results suggest a chaotic nature of ferromagnetic phase.
- Publication:
-
Physical Review B
- Pub Date:
- April 2004
- DOI:
- 10.1103/PhysRevB.69.144424
- arXiv:
- arXiv:cond-mat/0308247
- Bibcode:
- 2004PhRvB..69n4424S
- Keywords:
-
- 75.40.Gb;
- 75.50.Lk;
- 75.30.Kz;
- 75.70.Cn;
- Dynamic properties;
- Spin glasses and other random magnets;
- Magnetic phase boundaries;
- Magnetic properties of interfaces;
- Condensed Matter - Disordered Systems and Neural Networks
- E-Print:
- 14 pages, 16 figures, and 2 tables