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Abstracts
P2.21
Correlation between the components of resistance tensor in
disordered Nd
2
-xCexCuO
4
+
δ
as a manifestation of anisotropic pairing
symmetry.
Charikova Tatiana(1,2), Shelushinina Nina(1), Harus German(1), Petukhov
Denis(1), Petukhova Olga(1), Ivanov Andrey(3)
1) M.N.Mikheev Institute of Metal Physics Ural Branch of RAS, 620990,
Ekaterinburg, S.Kovakevskaya str., 18, Russia
2) Ural Federal University, Ekaterinburg, 620002, 19 Mira str., Russia
3) National Research Nuclear University MEPhI, 115409, Kashirskoe highway,
31, Moscow, Russia
The
ρxx
(
B
) and
ρxy
(
B
) of the electron-doped compounds
Nd
2
−
xCexCuO
4
+
δ
in under doped (x = 0.14) and optimally doped (x=0.15) regions near
antiferromagnetic (AF)-superconducting (SC) phase transition and with varying
degrees of disorder (
δ
) were investigated. In the under doped region where
the coexistence of the long-range AF fluctuations and SC occurs the scaling
relationship
ρxy
(
B
)
≈
ρxx
β
(
B
) gives
β
= 0
.
8–1
.
55 can be connected both with
a displaying of anisotropic s - or d - wave pairing symmetry and with a pinning
due to an essential degree of disorder. The value
β
≈
1 in optimally doped region
points out on the evidence of the d - wave pairing symmetry.
P2.22
Helical Majorana fermions in dx2–y2 + idxy-wave topological
superconductivity of doped correlated quantum spin Hall insulators
Sun Shih-Jye(1), Chung Chung-Hou Chung(2),(3), Chang Yung-Yeh Chang(2),
Tsai Wei-Feng Tsai(4), Zhang Fu-Chun Zhang(5),(6)
1) Department of Applied Physics, National University of Kaohsiung, Kaohsiung,
Taiwan, R.O.C.
2) Electrophysics Department, National Chiao-Tung University, HsinChu,
Taiwan, 300, R.O.C.
3) Physics Division, National Center for Theoretical Sciences, HsinChu, Taiwan,
300 R.O.C.
4) Department of Physics, National Sun Yat-Sen University, Kaohsiung, Taiwan,
R.O.C.
5) Department of Physics, Zhejiang University, Hangzhou, China.
6) Collaborative Innovation Center of Advanced Microstructures, Nanjing, China.
We propose a novel route for realizing Majorana fermions in 2D spin-singlet
topological superconducting state in doped correlated quantum spin Hall insulator,
relevant for adatom-doped graphene. Via a renormalized mean-field approach,
the system exhibits time-reversal symmetry breaking dx2
−
y2 + idxy-wave
superconductivity near half-filling. Surprisingly, at large spin-orbit coupling,
the system undergoes a topological phase transition to a new topological phase
protected by a pseudospin Chern number. Two pairs of counterpropagating
helical Majorana modes per edge, instead of two chiral propagating edge modes
in the d + id
0
superconductors, are realized.
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