Junlei Wang

Magnetization at the interface of Cr2O3and paramagnets with large stoner susceptibility

From the Cr 2p3/2 x-ray magnetic circular dichroism signal, there is clear evidence of interface polarization with overlayers of both Pd and Pt on chromia (Cr2O3). The residual boundary polarization of chomia is stronger for a Pt overlayer than in the case of a Pd overlayer. The reduction of chromia boundary magnetization with a paramagnetic metal overlayer, compared to the free surface, is interpreted as a response to the induced spin polarization in Pt and Pd. Magnetization induced in a Pt overlayer, via proximity to the chromia boundary magnetization, is evident in the polar magneto-optical Kerr measurements. These results are essential to explainations why Pt and Pd are excellent spacer layers for voltage controlled exchange bias, in the [Pd/Co] n /Pd/Cr2O3 and [Pt/Co] n /Pt/Cr2O3 perpendicular magneto-electric exchange bias systems. The findings pave the way to realize ultra-fast reversal of induced magnetization in a free moment paramagnetic layer, with possible application in voltage-controlled magnetic random access memory.

Magnetoelectric Fe 2TeO 6 thin films

We demonstrate that Fe2TeO6 is a magnetoelectric antiferromagnet with voltage-controllable boundary magnetization. This provides experimental evidence of the theoretical prediction that boundary magnetization is a universal property of magnetoelectric antiferromagnets including boundary magnetization at a surface orthogonal to the polar direction. Highly (110) textured Fe2TeO6 thin films were grown by pulsed laser deposition, terminating in Te-O at the (110) surface due to a surface reconstruction. Magnetic dc susceptibility measurements of both Fe2TeO6 powder and thin film samples confirm antiferromagnetic long-range order. Finally, measurements of x-ray magnetic circular dichroism combined with photoemission electron microscopy (XMCD-PEEM) provide a lower bound to the spin and angular magnetic moment of the surface Fe ions.

Magnetoelectric Fe2TeO6 thin films.

We demonstrate that Fe2TeO6 is a magnetoelectric antiferromagnet with voltage-controllable boundary magnetization. This provides experimental evidence of the theoretical prediction that boundary magnetization is a universal property of magnetoelectric antiferromagnets including boundary magnetization at a surface orthogonal to the polar direction. Highly (110) textured Fe2TeO6 thin films were grown by pulsed laser deposition, terminating in Te-O at the (110) surface due to a surface reconstruction. Magnetic dc susceptibility measurements of both Fe2TeO6 powder and thin film samples confirm antiferromagnetic long-range order. Finally, measurements of x-ray magnetic circular dichroism combined with photoemission electron microscopy (XMCD-PEEM) provide a lower bound to the spin and angular magnetic moment of the surface Fe ions.

Magnetoelectric Fe2TeO6thin films

We demonstrate that Fe2TeO6 is a magnetoelectric antiferromagnet with voltage-controllable boundary magnetization. This provides experimental evidence of the theoretical prediction that boundary magnetization is a universal property of magnetoelectric antiferromagnets including boundary magnetization at a surface orthogonal to the polar direction. Highly (110) textured Fe2TeO6 thin films were grown by pulsed laser deposition, terminating in Te-O at the (110) surface due to a surface reconstruction. Magnetic dc susceptibility measurements of both Fe2TeO6 powder and thin film samples confirm antiferromagnetic long-range order. Finally, measurements of x-ray magnetic circular dichroism combined with photoemission electron microscopy (XMCD-PEEM) provide a lower bound to the spin and angular magnetic moment of the surface Fe ions.