Abstract
In order to explore the physical properties of orthorhombic -type , we have carried out a combined study by means of the measurements of the magnetic susceptibility χ, electrical resistivity ρ, Seebeck coefficient S, and specific heat . An antiferromagnetic phase transition at the Néel temperature has been identified by all measured physical quantities. Remarkably, another intrinsic phase transition characterized by marked features has been discerned at . The distinct peak in at with the lack of thermal hysteresis behavior provides strong evidence for the second-order phase transition in nature. It is noticed that the observations near are reminiscent of a typical charge density wave (CDW) ordering. We compared the experimental results with those observed in a polymorph of with the tetragonal -type structure which was recently reported to exhibit the coexistence of magnetic and CDW phase transitions. On this basis, the observed features in orthorhombic have been discussed by comparing with the results in tetragonal as well as other CDW systems.
- Received 5 November 2019
- Revised 13 February 2020
- Accepted 13 April 2020
DOI:https://doi.org/10.1103/PhysRevB.101.155140
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