Murray Wilson

Chiral skyrmions in cubic helimagnet films: The role of uniaxial anisotropy

This paper reports on magnetometry and magnetoresistance measurements of MnSi epilayers performed in out-of-plane magnetic fields. We present a theoretical analysis of the chiral modulations that arise in confined cubic helimagnets where the uniaxial anisotropy axis and magnetic field are both out-of-plane. In contrast to in-plane field measurements (Wilson et al., Phys. Rev. B 86, 144420 (2012)), the hard-axis uniaxial anisotropy in MnSi/Si(111) increases the energy of (111)-oriented skyrmions and in-plane helicoids relative to the cone phase, and makes the cone phase the only stable magnetic texture below the saturation field. While induced uniaxial anisotropy is important in stabilizing skyrmion lattices and helicoids in other confined cubic helimagnets, the particular anisotropy in MnSi/Si(111) entirely suppresses these states in an out-of-plane magnetic field. However, it is predicted that isolated skyrmions with enlarged sizes exist in MnSi/Si(111) epilayers in a broad range of out-of-plane magnetic fields.

Surface twist instabilities and skyrmion states in chiral ferromagnets

IFW Dresden, Postfach 270016, D-01171 Dresden, Germany(Dated: May 22, 2014)In epitaxial MnSi/Si(111) films, the in-plane magnetization saturation is never reached due tothe formation of specific surface chiral modulations with the propagation direction perpendicularto the film surfaces [Wilson et al. Phys. Rev. B 88, 214420 (2013)]. In this paper we showthat the occurrence of such chiral surface twists is a general effect attributed to all bulk and con-fined magnetic crystals lacking inversion symmetry. We present experimental investigations of thisphenomenon in nanolayers of MnSi/Si(111) supported by detailed theoretical analysis within thestandard phenomenological model. In magnetic nanolayers with intrinsic or induced chirality, suchsurface induced instabilities become sizeable effects and play a crucial role in the formation ofskyrmion lattices and other nontrivial chiral modulations.

Uniaxial pressure effect on the magnetic ordered moment and transition temperatures in BaFe2-xTxAs2 ( T=Co,Ni )

We use neutron diffraction and muon spin relaxation to study the effect of in-plane uniaxial pressure on the antiferromagnetic (AF) orthorhombic phase in BaFe

Volume-wise destruction of the antiferromagnetic Mott insulating state through quantum tuning

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Cubic Re6+ (5d1) Double Perovskites, Ba2MgReO6, Ba2ZnReO6, and Ba2Y2/3ReO6: Magnetism, Heat Capacity, μSR, and Neutron Scattering Studies and Comparison with Theory

As

μSR study of the noncentrosymmetric superconductor PbTaSe2

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Neutron study of in-plane skyrmions in MnSi thin films

and its Co- and Ni-substituted members near optimal superconductivity. In the low temperature AF ordered state, uniaxial pressure necessary to detwin the orthorhombic crystals also increases the magnetic ordered moment, reaching an 11

New Fluoride-arsenide Diluted Magnetic Semiconductor (Ba,K)F(Zn,Mn)As with Independent Spin and Charge Doping

\%

Antiferromagnetism and hidden order in isoelectronic doping of URu2Si2

increase under 40 MPa for BaFe

Hidden order signatures in the antiferromagnetic phase of U(Ru1-xFex)2Si2

_{1.9}