In supersymmetric extension to the Standard Model (SM) of physics, a sfermion is a hypothetical spin-0 superpartner particle (sparticle) of its associated fermion.
[3][4] The name 'sfermion' was formed by the general rule of prefixing an 's' to the name of its superpartner, denoting that it is a scalar particle with spin 0.
One corollary from supersymmetry is that sparticles have the same gauge numbers as their SM partners.
Thus, sparticles must have different masses from the particle partners and supersymmetry is said to be broken.
These include the selectron, smuon, stau, and their corresponding sneutrino flavors.