  Persistent spin textures (PSTs) in solid-state materials arise from a
unidirectional spin-orbit field in momentum space and offer a route to deliver
long carrier spin lifetimes sought for future quantum microelectronic devices.
Nonetheless, few three-dimensional materials are known to host PSTs owing to
crystal symmetry and chemical requirements. There are even fewer examples
demonstrated experimentally. Here we report that high-quality persistent spin
textures can be obtained in the polar point groups containing an odd number of
mirror operations. We use representation theory analysis and electronic
structure calculations to formulate general discovery principles to identify
PSTs hidden in known complex ternary layered and perovskite structures with
large electric polarizations. We then show some of these materials exhibit PSTs
without requiring any special crystalline symmetries. This finding removes the
limitation imposed by mirror-symmetry protected PSTs that has limited compound
discovery. Our general design approach enables the pursuit of persistent spin
helices in materials exhibiting the $C_{3v}$ crystal class adopted by many
quantum materials exhibiting large Rashba coefficients.
