films*

Multi-functional thin films of boron (B) doped Cr₂O₃ grown by pulsed laser deposition exhibit voltage-controlled and nonvolatile Néel vector reorientation in the absence of a magnetic field. Isothermal toggling of antiferromagnetic states is demonstrated in prototype device structures at CMOS compatible temperatures between 300 K and 400 K. A strict determination of T_N is essential but has remained elusive most likely due to a thermally activated runaway effect of the Néel temperature. This behavior can be understood by considering the B-enrichment due to the phenomenon of surface segregation. Cold Neutron Depth Profiling (cNDP), performed at National Institute of Standards and Technology, points at progressing depletion of B in the bulk and B-accumulation near the surface. By using X-ray Photon Spectroscopy and Spin Hall measurements, we demonstrate a shift in T_N towards higher values of ≈ 477 K, associated with the increase in B-concentration within an interfacial layer of about 70 nm.