Distant neighbors exchange interactions in Cd1−xMnxTe

Abstract From magnetization measurements in bulk samples of Cd 1− x Mn x Te ( x ⩽3.6%), at T=20 mK , three new antiferromagnetic exchange constants, beyond the nearest-neighbors J 1 =−6.1±0.3 K , were measured. In order of decreasing strength, they are J (2) =−0.39±0.02, J (3) =−0.18±0.01 and J (4) =−0.06±0.01 K . Comparison of the data with theoretical simulations based on the cluster model with random distribution, made so far, has established that: (a) J (3) corresponds unequivocally to the third-neighbors constant J 3 ; (b) similar to the case of Zn-compounds (V. Bindilatti et al., Phys. Rev. Lett. 80 (1998) 5425), there is strong evidence that J (2) corresponds to J 4 , contrary to theoretical predictions.