We show that graphene with Mn adatoms trapped at single vacancies features spin-dependent Seebeck effect, thus enabling the use of this material for spin caloritronics. A gate potential can be used to tune its thermoelectric properties in a way it presents either a total spin polarized current, flowing in one given direction, or currents for both spins flowing in opposite directions without net charge transport. Moreover, we show that the thermal magnetoresistance can be tuned between −100% and +100% by varying a gate potential.

1.
G. E. W.
Bauer
,
E.
Saitoh
, and
B. J.
van Wees
,
Nature Mater.
11
,
391
(
2012
).
2.
K. S.
Novoselov
,
A. K.
Geim
,
S. V.
Morozov
,
D.
Jiang
,
Y.
Zhang
,
S. V.
Dubonos
,
I. V.
Grigorieva
, and
A. A.
Firsov
,
Science
306
,
666
(
2004
).
3.
V. M.
Karpan
,
G.
Giovannetti
,
P. A.
Khomyakov
,
M.
Talanana
,
A. A.
Starikov
,
M.
Zwierzycki
,
J.
van den Brink
,
G.
Brocks
, and
P. J.
Kelly
,
Phys. Rev. Lett.
99
,
176602
(
2007
).
4.
N.
Tombros
,
C.
Jozsa
,
M.
Popinciuc
,
H. T.
Jonkman
, and
B. J.
van Wees
,
Nature
448
,
571
(
2007
).
5.
D.
Dragoman
and
M.
Dragoman
,
Appl. Phys. Lett.
91
,
203116
(
2007
).
6.
B.
Zhou
,
B.
Zhou
,
Z.
Liu
, and
G.
Zhou
,
J. Appl. Phys.
112
,
073712
(
2012
).
7.
Y. M.
Zuev
,
W.
Chang
, and
P.
Kim
,
Phys. Rev. Lett.
102
,
096807
(
2009
).
9.
X.
Wu
,
Y.
Hu
,
M.
Ruan
,
N. K.
Madiomanana
,
C.
Berger
, and
W. A.
de Heer
,
Appl. Phys. Lett.
99
,
133102
(
2011
).
10.
M.
Zeng
,
Y.
Feng
, and
G.
Liang
,
Nano Lett.
11
,
1369
(
2011
).
11.
M.
Zeng
,
Y.
Feng
, and
G.
Liang
,
Appl. Phys. Lett.
99
,
123114
(
2011
).
12.
O.
Cretu
,
A. V.
Krasheninnikov
,
J. A.
Rodríguez-Manzo
,
L.
Sun
,
R. M.
Nieminen
, and
F.
Banhart
,
Phys. Rev. Lett.
105
,
196102
(
2010
).
13.
M. P.
Lima
,
A. J. R.
da Silva
, and
A.
Fazzio
,
Phys. Rev. B
84
,
245411
(
2011
).
14.
E. J. G.
Santos
,
A.
Ayuela
, and
D.
Sánchez-Portal
,
New J. Phys.
12
,
053012
(
2010
).
15.
C.
Cao
,
M.
Wu
,
J.
Jiang
, and
H.-P.
Cheng
,
Phys. Rev. B
81
,
205424
(
2010
).
16.
E. J. G.
Santos
,
D.
Sánchez-Portal
, and
A.
Ayuela
,
Phys. Rev. B
81
,
125433
(
2010
).
17.
A. V.
Krasheninnikov
,
P. O.
Lehtinen
,
A. S.
Foster
,
P.
Pyykkö
, and
R. M.
Nieminen
,
Phys. Rev. Lett.
102
,
126807
(
2009
).
18.
Y.
Tang
,
Z.
Yang
, and
X.
Dai
,
J. Chem. Phys.
135
,
224704
(
2011
).
19.
H.
Wang
,
Q.
Wang
,
Y.
Cheng
,
K.
Li
,
Y.
Yao
,
Q.
Zhang
,
C.
Dong
,
P.
Wang
,
U.
Schwingenschlgl
,
W.
Yang
, and
X. X.
Zhang
,
Nano Lett.
12
,
141
(
2012
).
20.
J. A.
Rodriguez-Manzo
and
F.
Banhart
,
Nano Lett.
9
,
2285
(
2009
).
21.
As the interatomic distance in an isolated Mn dimer is ≈3.3 Å,30,31 we only consider Mn in the substitutional sites of graphene with distances larger than this value in order to avoid direct Mn-Mn interactions.
22.
E.
Artacho
,
D.
Sánchez-Portal
,
P.
Ordejón
,
A.
García
, and
J. M.
Soler
,
Phys. Status Solidi B
215
,
809
(
1999
).
23.
F. D.
Novaes
,
A. J. R.
da Silva
, and
A.
Fazzio
,
Braz. J. Phys.
36
,
799
(
2006
);
J. E.
Padilha
,
M. P.
Lima
,
A. J. R.
da Silva
, and
A.
Fazzio
,
Phys. Rev. B
84
,
113412
(
2011
); the code has been modified to allow the use of graphical processing units (GPUs).
24.
J. P.
Perdew
,
K.
Burke
, and
M.
Ernzerhof
,
Phys. Rev. Lett.
77
,
3865
(
1996
).
25.
N.
Troullier
and
J. L.
Martins
,
Phys. Rev. B
43
,
1993
(
1991
).
26.
H. J.
Monkhorst
and
J. D.
Pack
,
Phys. Rev. B
13
,
5188
(
1976
).
27.
This potential consists of a plateau, U(z) = eVg for z0<z<z1, represented by a dashed line in Fig. 1(a), with smooth sinusoidal steps with width τ, indicated by the dotted lines in Fig. 1(a). U(z) = 0 elsewhere. In the calculations we defined the gated region trough z0 = 11.24 Å, z1 = 21.23 Å and τ=1.25 Å.
28.
M.
Büttiker
,
Y.
Imry
,
R.
Landauer
, and
S.
Pinhas
,
Phys. Rev. B
31
,
6207
(
1985
);
M.
Büttiker
,
Phys. Rev. Lett.
57
,
1761
(
1986
).
[PubMed]
29.
U.
Sivan
and
Y.
Imry
,
Phys. Rev. B
33
,
551
(
1986
).
30.
V. A.
Rigo
,
R. H.
Miwa
,
A. J. R.
da Silva
, and
A.
Fazzio
,
J. Appl. Phys.
109
,
053715
(
2011
).
31.
S.
Yamamoto
,
H.
Tatewaki
,
H.
Moriyama
, and
H.
Nakano
,
J. Chem. Phys.
124
,
124302
(
2006
).
You do not currently have access to this content.