Spin-glass phases in stage-2FeCl3graphite intercalation compound

Abstract

The magnetic phase transitions of stage-2 FeCl 3 graphite intercalation compound have been studied using superconducting quantum interference device dc and ac susceptibility measurements in the temperature range between 1.9 and 18 K. The temperature, frequency, and field dependence of aa Ј , aa Љ , cc Ј , and cc Љ clearlyshow that this compound undergoes two kinds of spin-glass phase transition at T SG (h) (Ϸ4.5-6.1 K) and T SG (l) (Ϸ2 -2.5 K), respectively. Both aa Љ and cc Љ have peaks at T SG (h) that shift to the low-temperature side with decreasing frequency. The spin-glass phase below T SG (h) may result from a competition between the antiferromagnetic XY -like Fe 3ϩ spins as the majority and the ferromagnetic Ising Fe 2ϩ spins as the minority. The absorption aa Љ has a peak at T SG (l) that shifts to the low-temperature side with decreasing frequency. No anomaly in cc Љ is observed at T SG (l) , indicating that only the XY components of spins contribute to this transition. The spin-glass transition below T SG (l) may result from a competition between the intraplanar nearest-neighbor antiferromagnetic and next-nearest-neighbor ferromagnetic intraplanar exchange interaction, which is responsible for a possible incommensurate in-plane spin structure at low temperatures. ͓S0163-1829͑98͒01725-1͔

Magnetic phase diagram and cluster glasslike properties of stage-1 graphite-intercalated FeCl3

“…Thus, in this system, the magnetic correlations are strictly 2D in nature, although they can be described using the same modulation vector as for the stage-1 compound [12]. Both stage-2 and stage-3 compounds show spin-glass-like behavior [8]. For the stage-3 compound, AC magnetic susceptibility hints at a spin-glass state emerging at a characteristic temperature that increases with increasing frequency f and is equal to 3.7 K for f = 3.7 Hz [20].…”

“…1 together with the fit obtained using the Le Bail method in the JANA2006 software package [21]. Graphite intercalation compounds can be identified and checked for stage uniformity by inspecting the 00 diffraction peaks [8,20,22]. Our sample shows a single set of 00 peaks with a c-axis lattice parameter 054418-2 FIG.…”

“…For the stage-3 compound, AC magnetic susceptibility hints at a spin-glass state emerging at a characteristic temperature that increases with increasing frequency f and is equal to 3.7 K for f = 3.7 Hz [20]. For the stage-2 compound, two separate spin-glass-like transitions have been reported at T h ≈ 4.5-6.1 K and T l ≈ 2-2.5 K, which also shift to higher temperatures with increasing frequency [8].…”

“…As the magnetic interlayer exchange coupling diminishes with increasing distance between the magnetic layers, the staging phenomenon provides a mechanism for investigating the crossover from 3D to 2D magnetic behavior. For this reason, GICs have been considered model systems for the study of 2D magnetism [8,9]. * j.levinsky@rug.nl…”

The quantum Dzyaloshinskii–Moriya spin glass model with uniaxial anisotropy in applied field

“…This interaction describes the scattering of the conduction electrons of the host (Cu) by Mn spins via the spin-orbit exchange of the non-magnetic impurity. The influence of the DM interaction has been investigated by Monte Carlo simulations for classical spin glass system [5][6][7][8], as well as by analytical studies with random DM exchange [9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27].…”