"Topological properties of superfluid 3He probed by surface electron bubbles" Kimitoshi Kono

Superfluid ³He is known as a p-wave superfluid, so that it is topological.  In the A phase of superfluid ³He the scattering of quasiparticles from small object is predicted to be skew with respect to an anisotropy axis, reflecting the chiral nature [1].  In the vicinity of the specular surface of the B-phase, the Majorana states, one of the edge states of topological matters, are predicted [2].

In this talk, we present our recent transport measurement of electron bubbles trapped below the free surface of superfluid ³He.  A direct experimental evidence of the chirality in superfluid ³He-A is obtained, for the first time [3].  The skew scattering of quasiparticles in ³He-A from an electron bubble resulted in a transverse transport which is analogous to the classical Hall effect, where the anisotropy vector plays a role of magnetic field.  The mobility measurement in the B-phase is found consistent with the Majorana surface states [4].

[1] R. H. Salmelin, M. M. Salomaa, and V. P. Mineev: Phys. Rev. Lett. 63, 868-871 (1989).

[2] S. B. Chung and S. C. Zhang: Phys. Rev. Lett. 103, 235301 (2009).

[3] H. Ikegami, Y. Tsutsumi, and K. Kono: Science 341, 59 (2013).

[4] H. Ikegami, S. B. Chung, and K. Kono: J.Phys. Soc.  Jpn. 82, 124607 (2013).