The electronic and atomic structure of substitutional nitrogen pairs, triplets, and clusters in GaP and GaAs is studied using the multiband empirical pseudopotential method with atomistically relaxed supercells. A single nitrogen impurity creates a localized a1(N) gap state in GaP, but in GaAs, the state is resonant above the conduction-band minimum. We show how the interaction of multiple a1 impurity levels, for more than one nitrogen, results in a nonmonotonic relationship between energy level and impurity separation. We assign the lowest (NN1) line in GaP to a [2,2,0] oriented pair, the second (NN2) line to a triplet of nitrogen atoms, and identify the origin of a deeper observed level as an [1,1,0] oriented triplet. We also demonstrate that small nitrogen clusters readily create very deep levels in both GaP and GaAs.

1.
X.
Liu
,
M.-E.
Pistol
, and
L.
Samuelson
,
Phys. Rev. B
42
,
7504
(
1990
).
2.
R.
Schwabe
,
W.
Seifert
,
F.
Bugge
,
R.
Bindemann
,
V. F.
Agekyan
, and
S. V.
Pogarev
,
Solid State Commun.
55
,
167
(
1985
).
3.
S.
Francoeur
,
S. A.
Nikishin
,
C.
Jin
,
Y.
Qiu
, and
H.
Temkin
,
Appl. Phys. Lett.
75
,
1538
(
1999
).
4.
D. G.
Thomas
,
J. J.
Hopfield
, and
C. J.
Frosch
,
Phys. Rev. Lett.
15
,
857
(
1965
).
5.
J. J.
Hopfield
,
D. G.
Thomas
, and
R. T.
Lynch
,
Phys. Rev. Lett.
17
,
312
(
1966
).
6.
E.
Cohen
and
M. D.
Sturge
,
Phys. Rev. B
15
,
1039
(
1977
).
7.
B.
Gil
,
M.
Baj
,
J.
Camassel
,
H.
Mathieu
,
C.
Benoit á la Guillaume
,
N.
Mestres
, and
J.
Pascual
,
Phys. Rev. B
29
,
3398
(
1984
).
8.
B.
Gil
,
J.
Camassel
,
J. P.
Albert
, and
H.
Mathieu
,
Phys. Rev. B
33
,
2690
(
1986
).
9.
H. P.
Xin
and
C. W.
Tu
,
Appl. Phys. Lett.
76
,
1267
(
2000
).
10.
K.
Mäder
and
A.
Zunger
,
Appl. Phys. Lett.
64
,
2882
(
1994
).
11.
P.
Leroux-Hugon
and
H.
Mariette
,
Phys. Rev. B
30
,
1622
(
1984
).
12.
Y.
Zhang
and
A.
Mascarenhas
,
Phys. Rev. B
61
,
15562
(
2000
).
13.
Y.
Zhang
,
B.
Fluegel
,
A.
Mascarenhas
,
H. P.
Xin
, and
C. W.
Tu
,
Phys. Rev. B
62
,
4493
(
2000
).
14.
M.
Kozhevnikov
,
V.
Narayanamurti
,
C. V.
Reddy
,
H. P.
Xin
,
C. W.
Tu
,
A.
Mascarenhas
, and
Y.
Zhang
,
Phys. Rev. B
61
,
R7861
(
2000
).
15.
Y.
Zhang
,
A.
Mascarenhas
,
H. P.
Xin
, and
C. W.
Tu
,
Phys. Rev. B
61
,
4433
(
2000
).
16.
M.
Kondow
,
K.
Uomi
,
A.
Niwa
,
T.
Kitatani
,
S.
Watahiki
, and
Y.
Yazawa
,
Jpn. J. Appl. Phys., Part 1
35
,
1273
(
1996
).
17.
L.
Wang
and
A.
Zunger
,
J. Chem. Phys.
100
,
2394
(
1994
).
18.
P. J.
Klar
,
H.
Grüning
,
W.
Heimbrodt
,
J.
Koch
,
F.
Höhnsdorf
,
W.
Stolz
,
P. M. A.
Vicente
, and
J.
Camassel
,
Appl. Phys. Lett.
76
,
3439
(
2000
).
19.
T.
Mattila
,
L.-W.
Wang
, and
A.
Zunger
,
Phys. Rev. B
59
,
15270
(
1999
);
P. R. C.
Kent
and
A.
Zunger
,
Phys. Rev. B
64
,
115208
(
2001
).
20.
J.
Shen
,
Y. R.
Shan
, and
J. D.
Dow
,
Phys. Rev. B
42
,
9119
(
1990
).
21.
C.
Benoit á la Guillaume
,
Physica B & C
117/118B
,
105
(
1983
).
22.
S.
Miyoshi
,
H.
Yaguchi
,
K.
Onabe
,
R.
Ito
, and
Y.
Shiraki
,
J. Cryst. Growth
145
,
87
(
1994
).
23.
H.
Saito
,
T.
Makimoto
, and
N.
Kobayashi
,
J. Cryst. Growth
170
,
372
(
1997
).
24.
R. A.
Faulkner
,
Phys. Rev.
175
,
991
(
1968
).
25.
J. W.
Allen
,
J. Phys. C
1
,
1136
(
1968
).
26.
B.
Gil
and
H.
Mariette
,
Phys. Rev. B
35
,
7999
(
1987
).
This content is only available via PDF.
You do not currently have access to this content.