Electron tunneling experiments were performed on p-Co1−xFexSb3–Al-oxide–Al junctions for x=0 and x=0.1 at 4.2 K. A U-shaped tunneling conductance curve obtained for polycrystalline p-CoSb3 clearly shows an energy-band gap of ∼50 meV. For p-Co0.9Fe0.1Sb3 skutterudites, a strong zero-bias conductance anomaly is observed. This anomaly may be due to a structural disorder arising from defects such as vacancies and interstitial Fe atoms.

1.
T. Caillat, A. Borschevsky, and J. P. Fleurial, in Proceedings of the 11th International Conference on Thermoelectrics, Arlington, TX, 1993, edited by R. Rao (University of Texas, Arlington, 1993), p. 98.
2.
D. T.
Morelli
,
T.
Caillat
,
J. P.
Fleurial
,
A.
Borschevsky
,
J.
Vandersande
,
B.
Chen
, and
S.
Uher
,
Phys. Rev. B
51
,
9622
(
1995
).
Google Scholar
 
3.
D.
Mandrus
,
A.
Migliori
,
T. W.
Darling
,
M. F.
Hundley
,
E. J.
Peterson
, and
J. D.
Thompson
,
Phys. Rev. B
52
,
4926
(
1995
).
Google Scholar
 
4.
T.
Caillat
,
A.
Borschevsky
, and
J. P.
Fleurial
,
J. Appl. Phys.
80
,
4442
(
1996
).
Google Scholar
 
5.
G. S.
Nolas
,
D. T.
Morelli
, and
T.
Tritt
,
Annu. Rev. Mater. Sci.
29
,
82
(
1999
).
Google Scholar
 
6.
D. T.
Morelli
,
G. P.
Meisner
,
B.
Chen
,
S.
Hu
, and
C.
Uher
,
Phys. Rev. B
56
,
7376
(
1997
).
Google Scholar
 
7.
G. S.
Nolas
,
J. L.
Cohn
, and
G. A.
Slack
,
Phys. Rev. B
58
,
164
(
1998
).
Google Scholar
 
8.
K. L.
Stokes
,
A. C.
Ehrich
, and
G. S.
Nolas
,
Mater. Res. Soc. Symp. Proc.
545
,
339
(
1999
).
Google Scholar
 
9.
S.
Katsuyama
,
Y.
Shichijo
,
M.
Ito
,
K.
Majima
, and
H.
Nagai
,
J. Appl. Phys.
84
,
6708
(
1998
).
Google Scholar
 
10.
J. Yang, G. P. Meisner, and C. Uher, in Proceedings of the 18th International Conference on Thermoelectrics, Baltimore, Maryland, 1999 (in press).
11.
H. Anno, T. Tashiro, and K. Matsubara, in Proceedings of the 18th International Conference on Thermoelectrics, Baltimore, Maryland, 1999 (in press).
12.
E. L. Wolf, Principles of Electron Tunneling Spectroscopy (Oxford University, New York, 1985), p. 46.
13.
Y.
Sawatari
,
N.
Suzuki
, and
Y.
Togami
,
Jpn. J. Appl. Phys.
10
,
164
(
1977
).
Google Scholar
 
14.
J.
Nagao
,
H.
Unuma
,
E.
Hatta
, and
K.
Mukasa
,
Phys. Status Solidi B
213
,
253
(
1999
).
Google Scholar
 
15.
F. Funagaki, Y. Miyahara, H. Ozaki, and V. A. Kulbachinskii, in Proceedings of the 15th International Conference on Thermoelectrics, Pasadena, CA, 1996, edited by T. Caillat, A. Borshchevsky, and J.-P. Fleurial (IEEE, Piscataway, NJ, 1996), pp. 408–411.
16.
H.
Anno
,
K.
Hatada
,
H.
Shimizu
,
K.
Matsubara
,
Y.
Notohara
,
T.
Sakakibara
,
H.
Tashiro
, and
K.
Motoya
,
J. Appl. Phys.
83
,
5270
(
1998
).
Google Scholar
 
17.
G. Petzow, Metallographisches Ätzen (Gebrüder Borntraeger, Berlin, 1976).
18.
D. J.
Singh
and
W. E.
Pickett
,
Phys. Rev. B
50
,
11235
(
1994
).
Google Scholar
 
19.
H.
Rakoto
,
M.
Respaud
,
J. M.
Broto
,
E.
Arushanov
, and
T.
Caillat
,
Physica B
269
,
13
(
1999
).
Google Scholar
 
20.
E.
Hatta
,
M.
Tonokawa
,
J.
Nagao
, and
K.
Mukasa
,
Solid State Commun.
102
,
437
(
1997
).
Google Scholar
 
21.
B. L.
Alshuler
and
A. G.
Aronov
,
Solid State Commun.
30
,
115
(
1979
).
Google Scholar
 
This content is only available via PDF.
© 2000 American Institute of Physics.
2000
American Institute of Physics
You do not currently have access to this content.