Topological nodal line in superfluid $^3$He and the Anderson theorem
2019
We have found an experimental evidence for the existence of the Dirac nodal line in the quasiparticle spectrum of the polar phase of superfluid $^3$He. The polar phase is stabilized by confinement of $^3$He between nm-sized cylinders. The temperature dependence of the gap, measured via frequency shift in the NMR spectrum, follows expected $\propto T^3$ dependence. The results support the Fomin extension of the Anderson theorem to the polar phase with columnar defects: perfect columnar non-magnetic defects do no perturb the magnitude of the gap in the polar phase. The existence of the node line opens possibilities to study Bogoliubov Fermi surfaces and flat-band fermions in the polar phase.
Keywords:
- Correction
- Source
- Cite
- Save
- Machine Reading By IdeaReader
15
References
3
Citations
NaN
KQI