Detecting the Majorana Fermion Surface State of He3-B through Spin Relaxation

The Majorana fermion, which can be useful for topological quantum computation, has eluded detection. He3-B, recently shown to be a time-reversal invariant topological superfluid, has a gapless Majorana fermion surface state. We show here that an electron spin relaxation experiment can detect this surface state—its Majorana nature through the Zeeman field direction dependence of the relaxation time 1/T₁∝sin⁡²θ, where θ is the angle between the field and the surface normal. We propose an experimental setup where an electron inside a nanobubble is injected below the He3 liquid surface.