  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.
