Carbon (C)-doping has been found to increase the upper critical field HC2 in superconducting MgB2 thin-film and bulk samples. However, the C effects on both HC2 and lattice parameters are very different between thin films and bulk, suggesting C may incorporate differently in the two cases. This paper combines ab initio calculations and thin-film lattice parameter measurements to explore the connection between substitutional and interstitial C in MgB2 and experimental bulk and thin-film lattice parameters.

1.
A.
Gurevich
,
S.
Patnaik
,
V.
Braccini
,
K. H.
Kim
,
C.
Mielke
,
X.
Song
,
L. D.
Cooley
,
S. D.
Bu
,
D. M.
Kim
,
J. H.
Choi
,
L. J.
Belenky
,
J.
Giencke
,
M. K.
Lee
,
W.
Tian
,
X. Q.
Pan
,
A.
Siri
,
E. E.
Hellstrom
,
C. B.
Eom
, and
D. C.
Larbalestier
,
Supercond. Sci. Technol.
17
,
278
(
2004
).
2.
J.
Nagamatsu
,
N.
Nakagawa
,
T.
Muranaka
,
Y.
Zenitani
, and
J.
Akimitsu
,
Nature (London)
410
,
63
(
2001
).
3.
V.
Braccini
,
A.
Gurevich
,
J. E.
Giencke
,
M. C.
Jewell
,
C. B.
Eom
,
D. C.
Larbalestier
,
A.
Pogrebnyakov
,
Y.
Cui
,
B. T.
Liu
,
Y. F.
Hu
,
J. M.
Redwing
,
Q.
Li
,
X. X.
Xi
,
R. K.
Singh
,
R.
Gandikota
,
J.
Kim
,
B.
Wilkens
,
N.
Newman
,
J.
Rowell
,
B.
Moeckly
,
V.
Ferrando
,
C.
Tarantini
,
D.
Marre
,
M.
Putti
,
C.
Ferdeghini
,
R.
Vaglio
, and
E.
Haanappel
,
Phys. Rev. B
71
,
012504
(
2005
).
4.
Y.
Zhu
,
D. C.
Larbalestier
,
P. M.
Voyles
,
A. V.
Pogrebnyakov
,
X. X.
Xi
, and
J. M.
Redwing
,
Appl. Phys. Lett.
91
,
082513
(
2007
).
5.
M. D.
Sumption
,
M.
Bhatia
,
M.
Rindfleisch
,
M.
Tomsic
,
S.
Soltanian
,
S. X.
Dou
, and
E. W.
Collings
,
Appl. Phys. Lett.
86
,
102501
(
2005
).
6.
A. V.
Pogrebnyakov
,
X. X.
Xi
,
J. M.
Redwing
,
V.
Vaithyanathan
,
D. G.
Schlom
,
A.
Soukiassian
,
S. B.
Mi
,
C. L.
Jia
,
J. E.
Giencke
,
C. B.
Eom
,
J.
Chen
,
Y. F.
Hu
,
Y.
Cui
, and
Q.
Li
,
Appl. Phys. Lett.
85
,
2017
(
2004
).
7.
S.
Lee
,
T.
Masui
,
A.
Yamamoto
,
H.
Uchiyama
, and
S.
Tajima
,
Physica C
397
,
7
(
2003
);
S. M.
Kazakov
,
R.
Puzniak
,
K.
Rogacki
,
A. V.
Mironov
,
N. D.
Zhigadlo
,
J.
Jun
,
C.
Soltmann
,
B.
Batlogg
, and
J.
Karpinski
,
Phys. Rev. B
71
,
024533
(
2005
);
B. J.
Senkowicz
,
J. E.
Giencke
,
S.
Patnaik
,
C. B.
Eom
,
E. E.
Hellstrom
, and
D. C.
Larbalestier
,
Appl. Phys. Lett.
86
,
202502
(
2005
).
8.
W. K.
Yeoh
,
J.
Horvat
,
J. H.
Kim
,
X.
Xu
, and
S. X.
Dou
,
Appl. Phys. Lett.
90
,
122502
(
2007
).
9.
Y. F.
Yan
and
M. M.
Al-Jassim
,
J. Appl. Phys.
92
,
7687
(
2002
).
10.
A.
Saengdeejing
,
J. E.
Saal
,
Y.
Wang
, and
Z. K.
Liu
,
Appl. Phys. Lett.
90
,
151920
(
2007
).
11.
G.
Kresse
and
J.
Furthmuller
,
Comput. Mater. Sci.
6
,
15
(
1996
).
12.
G.
Kresse
and
D.
Joubert
,
Phys. Rev. B
59
,
1758
(
1999
);
P. E.
Blöchl
,
Phys. Rev. B
50
,
17953
(
1994
).
13.
G.
Kresse
and
J.
Hafner
,
Phys. Rev. B
47
,
558
(
1993
);
G.
Kresse
and
J.
Furthmuller
,
Phys. Rev. B
54
,
11169
(
1996
).
14.
J. P.
Perdew
,
K.
Burke
, and
M.
Ernzerhof
,
Phys. Rev. Lett.
77
,
3865
(
1996
).
15.
S. H.
Wei
,
L. G.
Ferreira
,
J. E.
Bernard
, and
A.
Zunger
,
Phys. Rev. B
42
,
9622
(
1990
).
16.
A.
van de Walle
,
M.
Asta
, and
G.
Ceder
,
CALPHAD: Comput. Coupling Phase Diagrams Thermochem.
26
,
539
(
2002
).
17.
See supplementary material at http://dx.doi.org/10.1063/1.3275867E-JAPIAU-107-037001 for information on the computational and interstitial sites for all C concentrations.
18.
J. R.
Taylor
,
An Introduction to Error Analysis: The Study of Uncertainties in Physical Measurements
, 2nd ed. (
University Science Books
,
Sausalito
,
1982
).

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