Abstract
Thermodynamic experiments as well as Raman scattering have been used to study the magnetic instabilities in the spin-tetrahedra systems Cu2Te2O5X2, X =Cl and Br. While the phase transition observed in the Cl system at TN = 18.2K is consistent with 3D antiferromagnetic ordering, the phase transition at To = 11.4K in the Br system has several unusual features. We propose an explanation in terms of weakly coupled tetrahedra with a singlet-triplet gap and low-lying singlets.
| Original language | English |
|---|---|
| Pages (from-to) | 227201-227201-4 |
| Journal | Physical Review Letters |
| Volume | 87 |
| Issue number | 22 |
| DOIs | |
| State | Published - 26 Nov 2001 |
| Externally published | Yes |