@article{ISI:000476698100004,
 abstract = {The single helical Fermi surface on the surface state of
three-dimensional topological insulator Bi2Se3 is constrained by the
time-reversal invariant bulk topology to possess a spin-singlet
superconducting pairing symmetry. In fact, the Cu-doped and
pressure-tuned superconducting Bi2Se3 show no evidence of the
time-reversal symmetry (TRS) breaking. We report on the detection of the
TRS breaking in the topological superconductor Sr0.1Bi2Se3, probed by
zero-field mu SR measurements. The TRS breaking provides strong evidence
for the existence of a spin-triplet pairing state. The existence of TRS
breaking is also verified by longitudinal-field mu SR measurements,
which negates the possibility of magnetic impurities as the source of
TRS breaking. The temperature-dependent superfluid density deduced from
transverse-field mu SR measurements yields nodeless superconductivity
with low superconducting carrier density and penetration depth lambda =
1622(134) nm. From the microscopic theory of unconventional pairing, we
find that such a fully gapped spin-triplet pairing channel is promoted
by the complex interplay between the structural hexagonal warping and
higher order Dresselhaus spinorbit-coupling terms. Based on
Ginzburg-Landau analysis, we delineate the mixing of singlet- to
triplet-pairing symmetry as the chemical potential is tuned far above
from the Dirac cone. Our observation of such spontaneous TRS breaking
chiral superconductivity on a helical surface state, protected by the
TRS invariant bulk topology, can open avenues for interesting research
and applications.},
 article-number = {074201},
 author = {Neha, P. and Biswas, P. K. and Das, Tanmoy and Patnaik, S.},
 doi = {10.1103/PhysRevMaterials.3.074201},
 issn = {2475-9953},
 journal = {PHYSICAL REVIEW MATERIALS},
 month = {JUL 16},
 number = {7},
 orcid-numbers = {Patnaik, Satyabrata/0000-0003-4984-9243},
 times-cited = {0},
 title = {Time-reversal symmetry breaking in topological superconductor
Sr0.1Bi2Se3},
 unique-id = {ISI:000476698100004},
 volume = {3},
 year = {2019}
}