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Abstracts
P1.4
Quantum criticality in Kondo quantum dot coupled to helical edge
states of interacting 2D topological insulators
Chung Chung-Hou(1,2), Silotri Salman(1)
1) Department of Electrophysics, National Chiao-Tung University, HsinChu,
Taiwan, 300, R.O.C.
2) National Center for Theoretical Sciences, HsinChu, Taiwan 300, R.O.C.
We theoretically realize a novel quantum phase transition (QPT) between
the one-channel Kondo (1CK) and two-channel Kondo (2CK) fixed points in
a quantum dot coupled to helical edge states of interacting 2D topological
insulators, recently realized experimentally in InAs/GaSb bilayer. Combining
perturative renormalization group with bosonization techniques, we extract
critical properties of this quantum critical point (QCP). Our work offers the first
example of theoretically accessible 1CK-2CK QCP in soild state systems, and
sheds light on this long standing problem since 1990s’ in Kondo dot embedded
in conventional Luttinger wire due to its strong coupling nature.(NJP, 2015)
P1.5
Condensation energy as a function of doping for underdoped
YBa
2
Cu
3
O
6+
x
cuprates
Salas P., Sol´ıs M. A., Fortes M.
Instituto de F´ısica, Universidad Nacional Aut´onoma de M´exico Apdo. Postal
20-364, M´exico 1000 D. F. MEXICO
We report the condensation energy, the critical thermodynamic magnetic field
and the mass anisotropy for superconducting cuprates YBa
2
Cu
3
O
6+
x
, with
x
ranging from underdoping (
x
= 0
.
55) to optimally doped (
x
= 0
.
9). We apply
the Layered Boson-Fermion model of superconductivity [1], to model layered
superconductors such as cuprates. By minimizing the Helmholtz free energy of
the system, two optimal parameters of the model are determined, which are
the impenetrability of the planes and the paired fermion fraction. The obtained
results reproduce the experimental results within a 10 % error range.
[1] P. Salas, M. Fortes, M. A. Sol´ıs and F. J. Sevilla, Physica C
524
37 (2016).
We would like to thank support from grants CONACyT 221030 and
DGAPA-PAPIIT IN107616.
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