Jahn-Teller induced nematic orbital order in tetragonal Sr2VO4
نویسندگان
چکیده
Using high resolution x-ray diffraction (XRD) on high purity powders, we resolved the structure and ab symmetry of the intriguing compound Sr2VO4 from room temperature down to 20 K to an unprecedented level of accuracy. Upon cooling, this set of data unambiguously reveals a second-order phase transition lowering the symmetry from tetragonal to orthorhombic at a temperature Tc2 = 136 K. The observation of an orthorhombic distortion of the ab plane is attributed to nematic phase formation supported by local Jahn-Teller (JT) dynamical instability. At TN = 105 K, spins order and at Tc1 = 100 K the tetragonal structure is recovered with an elongated c axis.
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