ISSN:
1089-7550
Source:
AIP Digital Archive
Topics:
Physics
Notes:
The dilute insulating ferromagnet Fe1−xAsx[S2CN(C2H5)2]2Cl is examined in single crystal form for several compositions spanning the range x=0.014 to x=0.040. For x=0.0143 and x=0.0162 crystals, the inverse molar susceptibility along the [101] ferromagnetic easy axis is quite linear in temperature for T greater than a few times Tc. In the case of x=0.0313 and x=0.0402 crystals, in contrast, significant curvature appears in χ−1vs T throughout the 20–80 K temperature range. The initial (low-field) susceptibility along [101] for each crystal is measured in the critical region and analyzed via a standard power law form χ0=Γt−γ, where t=(T−Tc)/Tc. Tc decreases with increasing x, but somewhat slowly. The critical exponent γ increases with increasing x, from 1.19±0.01 near x=0.014 to 1.22±0.01 near x=0.040. The prefactor Γ is significantly smaller for the two higher As crystals, probably due to increased disorder. The variation in γ is not entirely unexpected, since the pure material, which is a candidate Z2xS1 system, has an unusual set of critical exponents, including a large positive α. Thus new critical behavior on dilution can occur by the Harris criterion. © 1996 American Institute of Physics.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.361691
