Abstract
An iron-selenide single crystal has been successfully synthesized using a self-flux method. The electrical resistivity measurement shows that this material exhibits semiconducting behavior in the whole temperature range, with an anomalous increment of resistivity at K. By varying the concentrations of Na and Fe, a small volume of superconducting phase could be achieved with a critical temperature of K. Structural characterization shows that, similarly to , the phase exhibits clear superstructure with a modulation wave vector of caused by the Fe-vacancy order within the a-b plane.
- Received 16 September 2014
- Revised 15 October 2014
DOI:https://doi.org/10.1103/PhysRevB.90.144519
©2014 American Physical Society