Spin Frustration Effect in Magnetic Graphite Intercalation Compounds

Abstract

The magnetic phase transition of stage-2 Cu_cCo_1-cCl₂ GIC's has been studied using SQUID AC magnetic susceptibility. For 0.4 ≤ c ≤ 0.9 the system undergoes a phase transition at T_cl and a reentrant spin glass transition at T_RSG (<T_cl). For 0.9<c ≤ 0.93 the system undergoes a spin glass transition at TSG from the paramagnetic phase to the spin glass phase. No phase transition is observed for c = 1 at least above 0.3 K. The nature of reentrant spin glass phase and spin glass phase is examined from the frequency dependence of absorption X″.

Key Words:

• spin frustration effect
• spin glass phase
• reentrant spin glass phase
• random spin system
• SQUID AC susceptibility