Observation of half-height magnetization steps in Sr2RuO4
  Spin-triplet superfluids can support exotic objects, such as half-quantum vortices characterized by the nontrivial winding of the spin structure. We present cantilever magnetometry measurements performed on mesoscopic samples of Sr2RuO4, a spin-triplet superconductor. For micron-sized annular-shaped samples, we observe transitions between integer fluxoid states, as well as a regime characterized by "half-integer transitions," i.e., steps in the magnetization with half the height of the ones we observe between integer fluxoid states. These half-height steps are consistent with the existence of half-quantum vortices in superconducting Sr2RuO4. 
J. Jang, D.G. Ferguson, V. Vakaryuk, R. Budakian, S.B. Chung, P.M.   Goldbart, and Y. Maeno
cond-mat.supr-con