We report on a study to determine the effect of waveguide sidewall roughness on quantum cascade (QC) laser performance using two two-wavelength heterogeneous QC laser structures, one with emission wavelengths of 7.0μm11.2μm, and the other with 8.7μm12.0μm. For the range of roughness standard deviation values from about 0.4to1.0μm, for which all four QC lasers were operating, the threshold current density increases by 12%–15% and the slope efficiency decreases by 30%–70% with stronger performance degradation for the shorter wavelength lasers, which is in agreement with a model based on Rayleigh scattering.

1.
N.
Daldosso
,
M.
Melchiorri
,
L.
Pavesi
,
G.
Puckier
,
F.
Gourbilleau
,
S.
Chausserie
,
A.
Belarouci
,
X.
Portier
, and
C.
Dufour
,
J. Lumin.
121
,
344
(
2006
).
2.
Y.
Wang
,
Z.
Lin
,
J.
Zhang
,
X.
Cheng
, and
F.
Zhang
,
Appl. Phys. B: Lasers Opt.
79
,
879
(
2004
).
3.
K. K.
Lee
,
D. R.
Lim
,
H. C.
Luan
,
A.
Agarwal
,
J.
Foresi
, and
L. C.
Kimerling
,
Appl. Phys. Lett.
77
,
1617
(
2000
).
4.
L.
Poladian
,
F.
Landouceur
, and
P. D.
Miller
,
J. Opt. Soc. Am. B
14
,
1339
(
1997
).
5.
F.
Ladouceur
,
J. D.
Love
, and
T. J.
Senden
,
IEE Proc.: Optoelectron.
14
,
242
(
1994
).
6.
D.
Marcuse
,
Bell Syst. Tech. J.
48
,
3187
(
1969
).
7.
P. K.
Tien
,
Appl. Opt.
10
,
2395
(
1971
).
8.
C. F.
Gmachl
,
F.
Capasso
,
D. L.
Sivco
, and
A. Y.
Cho
,
Rep. Prog. Phys.
64
,
1533
(
2001
).
9.
C. F.
Gmachl
,
D. L.
Sivco
,
J. N.
Baillargeon
,
A. L.
Hutchinson
,
F.
Capasso
, and
A. Y.
Cho
,
Appl. Phys. Lett.
79
,
572
(
2001
).
10.
F.
Toor
,
D. L.
Sivco
,
S. S.
Howard
, and
C. F.
Gmachl
(unpublished).
You do not currently have access to this content.