Structural and Magnetic Properties of Molecular Beam Epitaxy Grown Chromium Selenide Thin Films

Abstract

Chromium selenide thin films were grown epitaxially on Al${}_2$O${}_3$(0001) and Si(111)-(7$\times$7) substrates using molecular beam epitaxy (MBE). Sharp streaks in reflection high-energy electron diffraction and triangular structures in scanning tunneling microscopy indicate a flat smooth film growth along the c-axis, and is very similar to that from a hexagonal surface. X-ray diffraction pattern confirms the growth along the c-axis with c-axis lattice constant of 17.39 Å. The grown film is semiconducting, having a small band gap of about 0.034 eV, as calculated from the temperature dependent resistivity. Antiferromagnetic nature of the film with a Néel temperature of about 40 K is estimated from the magnetic exchange bias measurements. A larger out-of-plane exchange bias, along with a smaller in-plane exchange bias is observed below 40 K. Exchange bias training effects are analyzed based on different models and are observed to be following a modified power-law decay behavior.

14 Pages, 6 Figures + Supporting Information

References in corpus (3)

• Training Induced Positive Exchange Bias in NiFe/IrMn Bilayers
• Crystal structure and epitaxy of Bi2Te3 films grown on Si
• Anomalous Hall effect in two-dimensional non-collinear antiferromagnetic semiconductor Cr0.68Se