We report a very high average output power at room temperature for quantum-cascade lasers emitting at λ≈5.9 μm. For high-reflectivity-coated 2-mm-long cavities, a low threshold current density of 1.7 kA/cm2 was obtained at room temperature. From 300 to 400 K, the characteristic temperature (T0) was 198 K. A maximum average output power of 0.67 W was achieved. In addition, 0.56 W average output power was observed at a duty cycle of 56%.

1.
M. Razeghi, S. Slivken, J. S. Yu, A. Evans, and J. David, Fourth International Conference on Low Dimensional Structures and Devices (LDSD’02), Fortaleza, Brazil, 8–13 December 2002.
2.
S.
Slivken
,
Z.
Huang
,
A.
Evans
, and
M.
Razeghi
,
Appl. Phys. Lett.
80
,
4091
(
2002
).
3.
M.
Beck
,
D.
Hofstetter
,
T.
Aellen
,
J.
Faist
,
U.
Oesterle
,
M.
Ilegems
,
E.
Gini
, and
H.
Melchior
,
Science (Washington, DC, U.S.)
295
,
301
(
2002
).
4.
M.
Beck
,
J.
Faist
,
U.
Oesterle
,
M.
Ilegems
,
E.
Gini
, and
H.
Melchior
,
IEEE Photonics Technol. Lett.
12
,
1450
(
2000
).
5.
S.
Slivken
,
A.
Evans
,
J.
David
, and
M.
Razeghi
,
Appl. Phys. Lett.
81
,
4321
(
2002
).
6.
C. G.
Van de Walle
,
Phys. Rev. B
39
,
1871
(
1989
).
7.
J.
Faist
,
F.
Capasso
,
C.
Sirtori
,
D. L.
Sivco
,
A. L.
Hutchinson
, and
A. Y.
Cho
,
Appl. Phys. Lett.
66
,
538
(
1995
).
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