  30-80 nm thick yttrium iron garnet (YIG) films are grown by pulsed laser
deposition on a 5 nm thick sputtered Pt atop gadolinium gallium garnet
substrate (GGG) (110). Upon post-growth rapid thermal annealing, single crystal
YIG(110) emerges as if it were epitaxially grown on GGG(110) despite the
presence of the intermediate Pt film. The YIG surface shows atomic steps with
the root-mean-square roughness of 0.12 nm on flat terraces. Both Pt/YIG and
GGG/Pt interfaces are atomically sharp. The resulting YIG(110) films show clear
in-plane uniaxial magnetic anisotropy with a well-defined easy axis along <001>
and a peak-to-peak ferromagnetic resonance linewidth of 7.5 Oe at 9.32 GHz,
similar to YIG epitaxilly grown on GGG. Both spin Hall magnetoresistance and
longitudinal spin Seebeck effects in the inverted bilayers indicate excellent
Pt/YIG interface quality.
