Switching Magnetism and Superconductivity with Spin-Polarized Current in Iron-Based Superconductor

Abstract

We have explored a new mechanism for switching magnetism and superconductivity in a magnetically frustrated iron-based superconductor using spin-polarized scanning tunneling microscopy (SPSTM). Our SPSTM study on single crystal Sr${}_2$VO${}_3$FeAs shows that a spin-polarized tunneling current can switch the Fe-layer magnetism into a non-trivial $C_4$ (2$\times$2) order, not achievable by thermal excitation with unpolarized current. Our tunneling spectroscopy study shows that the induced $C_4$ (2$\times$2) order has characteristics of plaquette antiferromagnetic order in Fe layer and strongly suppressed superconductivity. Also, thermal agitation beyond the bulk Fe spin ordering temperature erases the $C_4$ state. These results suggest a new possibility of switching local superconductivity by changing the symmetry of magnetic order with spin-polarized and unpolarized tunneling currents in iron-based superconductors.

33 pages, 16 figures

References in corpus (11)

• Competing Orders and Spin-Density-Wave Instability in La(O${}_{1-x}$F${}_x$)FeAs
• Magnetism and its microscopic origin in iron-based high-temperature superconductors
• Iron-Based Superconductors: current status of materials and pairing mechanism
• Iron-based layered superconductor LaO${}_{1-x}$F${}_x$FeAs: an antiferromagnetic semimetal
• Superconductivity and spin-density-waves in multi-band metals
• Low-energy microscopic models for iron-based superconductors: a review
• Valley density-wave and multiband superconductivity in Fe-pnictides
• Self doping effect and successive magnetic transitions in superconducting Sr${}_2$VFeAsO${}_3$
• Suppression of superconductivity by V-doping and possible magnetic order in Sr2VO3FeAs
• Magnetic Ordering in V-Layers of the Superconducting System of Sr2VFeAsO3
• Magnetism and superconductivity in Sr${}_2$VFeAsO${}_3$ revealed by ${}^{75}$As- and ${}^{51}$V-NMR under elevated pressures

Cited by in corpus (1)

• Eliashberg theory for spin-fluctuations mediated superconductivity -- Application to bulk and monolayer FeSe