Majorana Fermions: Direct Observation in 3He

Abstract

In this letter we report the first direct observation of gap-less Majorana QPs which appear as Andreev bound states on the surface of superfluid $^3$He-B. We made the precise measurements of superfluid 3He-B heat capacity at the limit of extremely low temperatures. We have separated the heat capacity of bulk Bogolyubov QPs and the surface Majorana QPs by its different temperature dependence. We have found that at 0.11 mK the Majorana fermions constitute half of the bolometer heat capacity under the conditions of our experiments.