We employ properly designed asymmetric Mach-Zehnder interferometer structures as effective wavelength filters and monolithically integrate them in conventional Fabry-Perot cavities to facilitate single-mode operation of the lasers. With such asymmetric Mach-Zehnder interferometer type laser cavities, continuously tunable single-mode operation of quantum cascade (QC) lasers is achieved in pulsed mode from 80 K up to room temperature and in continuous-wave mode with side-mode suppression ratio up to ∼35 dB. These devices are fabricated with the same process as simple ridge lasers, therefore providing a promising solution to achieving more cost-effective single-mode QC lasers.

1.
K.
Namjou
,
S.
Cai
,
E. A.
Whittaker
,
J.
Faist
,
C.
Gmachl
,
F.
Capasso
,
D. L.
Sivco
, and
A. Y.
Cho
,
Opt. Lett.
23
,
219
221
(
1998
).
2.
G.
Wysocki
,
A. A.
Kosterev
, and
F. K.
Tittel
,
Appl. Phys. B
80
,
617
625
(
2005
).
3.
V.
Spagnolo
,
A. A.
Kosterev
,
L.
Dong
,
R.
Lewicki
, and
F. K.
Tittel
,
Appl. Phys. B
100
,
125
130
(
2010
).
4.
J.
Faist
,
C.
Gmachl
,
F.
Capasso
,
C.
Sirtori
,
D. L.
Sivco
,
J. N.
Baillargeon
, and
A. Y.
Cho
,
Appl. Phys. Lett.
70
,
2670
(
1997
).
5.
S.
Schartner
,
M.
Austerer
,
W.
Schrenk
,
A. M.
Andrews
,
P.
Klang
, and
G.
Strasser
,
Opt. Express
16
,
11920
11929
(
2008
).
6.
P.
Fuchs
,
J.
Friedl
,
S.
Höfling
,
J.
Koeth
,
A.
Forchel
,
L.
Worschech
, and
M.
Kamp
,
Opt. Express
20
,
3890
3897
(
2012
).
7.
R.
Colombelli
,
K.
Srinivasan
,
M.
Troccoli
,
O.
Painter
,
C. F.
Gmachl
,
D. M.
Tennant
,
A. M.
Sergent
,
D. L.
Sivco
,
A. Y.
Cho
, and
F.
Capasso
,
Science
302
,
1374
1377
(
2003
).
8.
G.
Wysocki
,
R. F.
Curl
,
F. K.
Tittel
,
R.
Maulini
,
J. M.
Billiard
, and
J.
Faist
,
Appl. Phys. B
81
,
769
(
2005
).
9.
P. Q.
Liu
,
X.
Wang
,
J.
Fan
, and
C.
Gmachl
,
Appl. Phys. Lett.
98
,
061110
(
2011
).
10.
P. Q.
Liu
,
K.
Sladek
,
X.
Wang
,
J.
Fan
, and
C. F.
Gmachl
,
Appl. Phys. Lett.
99
,
241112
(
2011
).
11.
Symmetric MZ interferometer type waveguide structures have been applied to QC lasers previously for different purposes, e.g., for sensing and power modulation see
L. K.
Hoffmann
,
M.
Austerer
,
E.
Mujagic
,
A. M.
Andrews
,
P.
Klang
,
W.
Schrenk
, and
G.
Strasser
,
J. Appl. Phys.
104
,
063110
(
2008
).
12.
M.
DiDomenico
,
IEEE J. Quantum Electron.
QE-2
,
311
322
(
1966
).
13.
Y. T.
Chieng
and
R. A.
Minasian
,
IEEE Photon. Technol. Lett.
6
,
153
156
(
1994
).
14.
E. L.
Wooten
,
R. L.
Stone
,
E. W.
Miles
, and
E. M.
Bradley
,
J. Lightwave Technol.
14
,
2530
2536
(
1996
).
15.
S.
Calvez
,
X.
Rejeaunier
,
P.
Mollier
,
J.-P.
Goedgebuer
, and
W. T.
Rhodes
,
J. Lightwave Technol.
19
,
893
898
(
2001
).
16.
M.
Schilling
,
K.
Dutting
,
W.
Idler
,
D.
Baums
,
G.
Laube
,
K.
Wunstel
, and
O.
Hilderbrand
,
Electron. Lett.
28
,
1698
1699
(
1992
).
17.
M.
Kuznetsov
,
P.
Verlangieri
,
A. G.
Dentai
,
C. H.
Joyner
, and
C. A.
Burrus
,
IEEE Photon. Technol. Lett.
4
,
1093
1095
(
1992
).
18.
L. K.
Hoffmann
,
C. A.
Hurni
,
S.
Schartner
,
M.
Austerer
,
E.
Mujagiæ
,
M.
Nobile
,
A.
Benz
,
W.
Schrenk
,
A. M.
Andrews
,
P.
Klang
, and
G.
Strasser
,
Appl. Phys. Lett.
91
,
161106
(
2007
).
19.
P. Q.
Liu
,
A. J.
Hoffman
,
M. D.
Escarra
,
K. J.
Franz
,
J. B.
Khurgin
,
Y.
Dikmelik
,
X.
Wang
,
J.
Fan
, and
C.
Gmachl
,
Nat. Photonics
4
,
95
98
(
2010
).
20.
K. J.
Franz
,
P. Q.
Liu
,
J. J. J.
Raftery
,
M. D.
Escarra
,
A. J.
Hoffman
,
S. S.
Howard
,
Y.
Yao
,
Y.
Dikmelik
,
X.
Wang
,
J.-Y.
Fan
,
J. B.
Khurgin
, and
C.
Gmachl
,
IEEE J. Quantum Electron.
46
,
591
600
(
2010
).
You do not currently have access to this content.