Chemical Manipulation of Magnetic Ordering in Mn1-xSnxBi2Se4 Solid-Solutions

Pierre F. Poudeu, University of Michigan Ann Arbor, DMR 1237550

Our investigation of the atomic structure and magnetism in the solid-solution series, Mn1-xSnxBi2Se4 (x = 0, 0.3, 0.75), revealed that although gradual Mn to Sn substitution within the Mn1-xSnxBi2Se4 series maintains the crystal structure as essentially unchanged, the magnetic behavior of the resulting material strongly depends on the distribution of the remaining Mn atoms throughout the various metal positions in the crystal structure. The dominant magnetic ordering within the Mn1-

xSnxBi2Se4 solid-solutions below 50K, switches from antiferromagnetic (AFM) for MnBi2Se4 (x = 0), to ferromagnetic (FM) for Mn0.7Sn0.3Bi2Se4 (x = 0.3), and finally to paramagnetic (PM) for Mn0.25Sn0.75Bi2Se4 (x = 0.75). [1] Ranmohotti; Djieutedjeu; Poudeu; J. Amer. Chem. Soc., 2012, accepted.

Graphical representation of crystal structure of Mn1−xSnxBi2Se4 ((A) x = 0; (C) x = 0.75) projected along [010] and geometrical details of the {Mn}nSe4n+2 single magnetic chain .

Magnetic behavior of various Mn1−xSnxBi2Se4 samples.

Our laboratory provides outstanding training on solid-state synthesis, structural characterization and evaluation of the electronic, thermal and magnetic properties, to undergraduate students, graduate students and postdoctoral research associate from various social groups involve in this research project. This year, one female African-American undergraduate student from Hope college (Michigan), Raisa Yewah, and a white male undergraduate student from the University of Michigan were heavily involved in the synthesis and characterization of new ferromagnetic semiconducting phases relevant to the project. In addition, one postdoctoral researcher and one graduate student (African American) were also supported by this award.

Chemical Manipulation of Magnetic Ordering in Mn1-xSnxBi2Se4 Solid-Solutions

Pierre F. Poudeu, University of Michigan Ann Arbor, DMR 1237550

Raisa (UG)Jeremy (UG)

Honore (G)

Pranati (G)

Erica (G)

Research training of undergraduate (UG) students and Graduate (G) students in Poudeu group (2011- 2012).