Spin glass in semiconducting KFe${}_{1.05}$Ag${}_{0.88}$Te${}_2$ single crystals

Abstract

We report discovery of KFe${}_{1.05}$Ag${}_{0.88}$Te${}_2$ single crystals with semiconducting spin glass ground state. Composition and structure analysis suggest nearly stoichiometric I4/mmm space group but allow for the existence of vacancies, absent in long range semiconducting antiferromagnet KFe${}_{0.85}$Ag${}_{1.15}$Te${}_2$. The subtle change in stoichometry in Fe/Ag sublattice changes magnetic ground state but not conductivity, giving further insight into the semiconducting gap mechanism.

5 pages, 4 figures