In this paper, we investigate the uniqueness of blowup at singular points of the free boundary in the superconductivity problem. We provide a sufficient condition and demonstrate that this condition can be verified in certain special cases. The proof of the main results in this paper is primarily based on Weiss-type and Monneau-type monotonicity formulas, and is inspired by the recent paper [Chen et al. arXiv: 2204.11426v2 (2022)].

1.
Berestycki
,
H.
,
Bonnet
,
A.
, and
Chapman
,
S. J.
, “
A semi-elliptic system arising in the theory of type-II superconductivity
,”
Comm. Appl. Nonlinear Anal.
1
(
3
),
1
21
(
1994
).
2.
Monneau
,
R.
and
Bonnet
,
A.
, “
Distribution of vortices in a type-II superconductor as a free boundary problem: Existence and regularity via Nash–Moser theory
,”
Interfaces Free Bound
2
(
2
),
181
200
(
2000
).
3.
Caffarelli
,
L. A.
, “
The obstacle problem revisited
,”
J. Fourier Anal. Appl.
4
(
4–5
),
383
402
(
1998
).
4.
Caffarelli
,
L. A.
and
Salazar
,
J.
, “
Solutions of fully nonlinear elliptic equations with patches of zero gradient: Existence, regularity and convexity of level curves
,”
Trans. Amer. Math. Soc.
354
(
8
),
3095
3115
(
2002
).
5.
Caffarelli
,
L. A.
and
Shahgholian
,
H.
, “
The structure of the singular set of a free boundary in potential theory
,”
Izv. Nats. Akad. Nauk Armenii Mat.
39
(
2
),
43
58
(
2004
).
6.
Caffarelli
,
L. A.
,
Salazar
,
J.
, and
Shahgholian
,
H.
, “
Free-boundary regularity for a problem arising in superconductivity
,”
Arch. Ration. Mech. Anal.
171
(
1
),
115
128
(
2004
).
7.
Chapman
,
S. J.
, “
A mean-field model of superconducting vortices in three dimensions
,”
SIAM J. Appl. Math.
55
(
5
),
1259
1274
(
1995
).
8.
Chapman
,
S. J.
,
Rubinstein
,
J.
, and
Schatzman
,
M.
, “
A mean-field model of superconducting vortices
,”
Eur. J. Appl. Math.
7
(
2
),
97
111
(
1996
).
9.
Chen
,
S.
,
Feng
,
Y.
, and
Li
,
Y.
, “
A note on the singular set of the no-sign obstacle problem
,” arXiv: 2204.11426v2 (
2022
).
10.
Elliott
,
M.
,
Stoth
,
B. E. E.
, and
Schätzle
,
R.
, “
Viscosity solutions of a degenerate parabolic-elliptic system arising in the mean-field theory of superconductivity
,”
Arch. Ration. Mech. Anal.
145
(
2
),
99
127
(
1998
).
11.
Fernandez-Real
,
X.
and
Ros-Oton
,
X.
,
PDE Regularity Theory for Elliptic
,
Zurich Lectures in Advanced Mathematics
(
EMS Press
,
Berlin
,
2022
).
12.
Figalli
,
A.
, “
Regularity of interfaces in phase transitions via obstacle problems
,” in
Proceedings of the International Congress of Mathematicians–Rio de Janeiro 2018
(
World Science. Publication
,
Hackensack, NJ
,
2018
),
Vol. I
, pp.
225
247
Plenary lectures.
13.
Figalli
,
A.
, “
Free boundary regularity in obstacle problems
,”
Journées équations aux dérivées partielles
2
,
1
26
(
2018
).
14.
Monneau
,
R.
, “
On the number of singularities for the obstacle problem in two dimensions
,”
J. Geom. Anal.
13
(
2
),
359
389
(
2003
).
15.
Monneau
,
R.
, “
On the regularity of a free boundary for a nonlinear obstacle problem arising in superconductor modelling
,”
Ann. Fac. Sci. Univ. Toulouse Sci. Math.
13
(
2
),
289
311
(
2004
).
16.
Petrosyan
,
A.
,
Shahgholian
,
H.
, and
Uraltseva
,
N.
,
Regularity of free boundaries in obstacle-type problems, Graduate Studies in Mathematics
(
American Mathematical Society
,
Providence, RI
,
2012
), Vol.
136
.
17.
Rodrigues
,
J.-F.
,
Obstacle Problems In Mathematical Physics, North-Holland Mathematics Studies
(
North-Holland Publishing Co.
,
Amsterdam
,
1987
), Vol.
134
.
18.
Sandier
,
E.
and
Serfaty
,
S.
, “
A rigorous derivation of a free-boundary problem arising in superconductivity
,”
Ann. Sci. Éc. Norm. Supér.
33
(
4
),
561
592
(
2000
).
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