Berlin 2015 – wissenschaftliches Programm
TT 71.57: Poster
Mittwoch, 18. März 2015, 15:00–18:00, Poster B
Resistivity of MnB4 — •Nico Steinki1, Dirk Schulze Grachtrup1, Stefan Süllow1, Arno Knappschneider2, and Barbara Albert2 — 1Institut für Physik der Kondensierten Materie, TU Braunschweig, Germany — 2Eduard-Zintl-Institut für Anorganische und Physikalische Chemie, TU Darmstadt, Germany
In an effort to develop super hard materials, MnB4 was recently synthesized for the first time in single crystalline form, with micro scale crystals of about 200 µm length. Subsequently, the magnetic properties have been studied experimentally, and band structure calculations have been carried out [1,2]. Based on these calculations and preliminary resistivity measurements, it was argued that the material is semiconducting, although a definite conclusion could not be reached.
In order to determine whether MnB4 is a semiconductor or a metal we have carried single crystal resistivity measurements at temperatures 2 to 300 K. For this purpose a setup for measuring micro-scale samples was developed and characterized. The setup is based on a modified two point configuration and the resistivity of MnB4 was measured as function of temperature. With these measurements MnB4 was identified to be a semiconductor.
 A. Knappschneider et al., Angew. Chem. 126 (2014) 1710
 H. Gou et al., Phys. Rev. B 89 (2014) 064108