3Experimental Physics V, Center for Electronic Correlations and Magnetism, Institute of Physics, University of Augsburg, D 86159 Augsburg, Germany
Received October 17, 2016
Ultrasound and magnetization studies of bond frustrated spinel HgCr2S4 are performed as a function of temperature in static magnetic fields. Beside the anharmonic effect, the sound velocity shows pronounced anomaly at the antiferromagnetic (AFM) transition at TN = 23 K with an additional significant increase of the order of 0.5% indicating a strong spin-lattice coupling. External magnetic fields enhance the ferromagnetic (FM) correlations and shift the anomalies to lower temperatures concomitantly with the reduction of the Néel temperature. The constructed H–T phase diagram beside the long-range AFM states reveals the state with induced FM order and regimes with short-range AFM and FM correlations as well.
PACS: 43.35.+d Ultrasonics, quantum acoustics, and physical effects of sound; PACS: 62.65.+k Acoustical properties of solids; PACS: 72.55.+s Magnetoacoustic effects; PACS: 75.50.Ee Antiferromagnetics; PACS: 75.60.Jk Magnetization reversal mechanisms.