  We report the generation and detection of spin-orbit torque ferromagnetic
resonance (STFMR) in micropatterned epitaxial Fe/Pt bilayers grown by molecular
beam epitaxy. The magnetic field dependent measurements at an in-plane magnetic
field angle of 45 degrees with respect to the microwave-current direction
reveal the presence of two distinct voltage peaks indicative of a strong
magnetic anisotropy. We show that STFMR can be employed to probe the underlying
magnetic properties including the anisotropies in the Fe layer. We compare our
STFMR results with broadband ferromagnetic resonance spectroscopy of the
unpatterned bilayer thin films. The experimental STFMR measurements are
interpreted using an analytical formalism and further confirmed using
micromagnetic modeling, which shed light on the field-dependent magnetization
alignment in the microstructures responsible for the STFMR rectification. Our
results demonstrate a simple and efficient method for determining magnetic
anisotropies in microstructures by means of rf spectroscopy.
