We report on the wavelength tuning dynamics in continuous-wave distributed feedback quantum cascade lasers (QCLs). The wavelength tuning response for direct current modulation of two mid-IR QCLs from different suppliers was measured from 10 Hz up to several MHz using ro-vibrational molecular resonances as frequency-to-intensity converters. Unlike the output intensity, which can be modulated up to several gigahertz, the frequency-modulation bandwidth was found to be on the order of 200 kHz, limited by the laser thermal dynamics. A non-negligible roll-off and a significant phase shift are observed above a few hundred hertz already and explained by a thermal model.
REFERENCES
1.
J.
Faist
, F.
Capasso
, D. L.
Sivco
, C.
Sirtori
, A. L.
Hutchinson
, and A. Y.
Cho
, “Quantum cascade laser
,” Science
264
(5158
), 553
–556
(1994
).2.
K.
Namjou
, S.
Cai
, E. A.
Whittaker
, J.
Faist
, C.
Gmachl
, F.
Capasso
, D. L.
Sivco
, and A. Y.
Cho
, “Sensitive absorption spectroscopy with a room-temperature distributed-feedback quantum-cascade laser
,” Opt. Lett.
23
(3
), 219
–221
(1998
).3.
T.
Aellen
, S.
Blaser
, M.
Beck
, D.
Hofstetter
, J.
Faist
, and E.
Gini
, “Continuous-wave distributed-feedback quantum-cascade lasers on a Peltier cooler
,” Appl. Phys. Lett.
83
, 1929
(2003
).4.
I.
Galli
, M. S.
de Cumis
, F.
Cappelli
, S.
Bartalini
, D.
Mazzotti
, S.
Borri
, A.
Montori
, N.
Akikusa
, M.
Yamanishi
, G.
Giusfredi
, P.
Cancio
, and P.
De Natale
, “Comb-assisted subkilohertz linewidth quantum cascade laser for high-precision mid-infrared spectroscopy
,” Appl. Phys. Lett.
102
, 121117
(2013
).5.
A.
Castrillo
, A.
Gambetta
, D.
Gatti
, G.
Galzerano
, P.
Laporta
, M.
Marangoni
, and L.
Gianfrani
, “Absolute molecular density determinations by direct referencing of a quantum cascade laser to an optical frequency comb
,” Appl. Phys. B
110
(2
), 155
–162
(2013
).6.
F.
Cappelli
, I.
Galli
, S.
Borri
, G.
Giusfredi
, P.
Cancio
, D.
Mazzotti
, A.
Montori
, N.
Akikusa
, M.
Yamanishi
, S.
Bartalini
, and P.
De Natale
, “Subkilohertz linewidth room-temperature mid-infrared quantum cascade laser using a molecular sub-Doppler reference
,” Opt. Lett.
37
, 4811
–4813
(2012
).7.
L.
Tombez
, J.
Di Francesco
, S.
Schilt
, G.
Di Domenico
, J.
Faist
, P.
Thomann
, and D.
Hofstetter
, “Frequency noise of free-running 4.6 μm distributed feedback quantum cascade lasers near room temperature
,” Opt. Lett.
36
, 3109
–3111
(2011
).8.
S.
Bartalini
, S.
Borri
, I.
Galli
, G.
Giusfredi
, D.
Mazzotti
, T.
Edamura
, N.
Akikusa
, M.
Yamanishi
, and P.
De Natale
, “Measuring frequency noise and intrinsic linewidth of a room-temperature DFB quantum cascade laser
,” Opt. Express
19
, 17996
–18003
(2011
).9.
R.
Paiella
, R.
Martini
, F.
Capasso
, C.
Gmachl
, H. Y.
Hwang
, D. L.
Sivco
, J. N.
Baillargeon
, A. Y.
Cho
, E. A.
Whittaker
, and H. C.
Liu
, “High-frequency modulation without the relaxation oscillation resonance in quantum cascade lasers
,” Appl. Phys. Lett.
79
, 2526
(2001
).10.
F.
Capasso
, R.
Paiella
, R.
Martini
, R.
Colombelli
, C.
Gmachl
, T. L.
Myers
, M. S.
Taubman
, R. M.
Williams
, C. G.
Bethea
, K.
Unterrainer
, H. Y.
Hwang
, D. L.
Sivco
, A. Y.
Cho
, A. M.
Sergent
, H. C.
Liu
, and E. A.
Whittaker
, “Quantum cascade lasers: Ultrahigh–speed operation, optical wireless communication, narrow linewidth, and far-infrared emission
,” IEEE J. Quantum Electron.
38
, 511
–532
(2002
).11.
S.
Kobayashi
, Y.
Yamamoto
, M.
Ito
, and T.
Kimura
, “Direct frequency modulation in AlGaAs semiconductor lasers
,” IEEE J. Quantum Electron.
18
(4
), 582
–595
(1982
).12.
P.
Vankwikelberge
, F.
Buytaert
, A.
Franchois
, R.
Baets
, P. I.
Kuindersma
, and C. W.
Fredriksz
, “Analysis of the carrier-induced FM response of DFB lasers: Theoretical and experimental case studies
,” IEEE J. Quantum Electron.
25
(11
), 2239
–2254
(1989
).13.
T.
Aellen
, R.
Maulini
, R.
Terazzi
, N.
Hoyler
, M.
Giovannini
, J.
Faist
, S.
Blaser
, and L.
Hvozdara
, “Direct measurement of the linewidth enhancement factor by optical heterodyning of an amplitude-modulated quantum cascade laser
,” Appl. Phys. Lett.
89
, 091121
(2006
).14.
L.
Tao
, K.
Sun
, D.
Miller
, M.
Khan
, and M.
Zondlo
, “Current and frequency modulation characteristics for continuous-wave quantum cascade lasers at 9.06 μm
,” Opt. Lett.
37
, 1358
–1360
(2012
).15.
S.
Borri
, S.
Bartalini
, P. C.
Pastor
, I.
Galli
, G.
Giusfredi
, D.
Mazzotti
, M.
Yamanishi
, and P.
De Natale
, “Frequency-noise dynamics of mid-infrared quantum cascade lasers
,” IEEE J. Quantum Electron.
47
(7
), 984
–988
(2011
).16.
L.
Tombez
, S.
Schilt
, J.
Di Francesco
, P.
Thomann
, and D.
Hofstetter
, “Temperature dependence of the frequency noise in a mid-IR DFB quantum cascade laser from cryogenic to room temperature
,” Opt. Express
20
, 6851
–6859
(2012
).17.
A.
Lops
, V.
Spagnolo
, and G.
Scamarcio
, “Thermal modeling of GaInAs/AlInAs quantum cascade lasers
,” J. Appl. Phys.
100
, 043109
(2006
).18.
M. S.
Vitiello
, T.
Gresch
, A.
Lops
, V.
Spagnolo
, G.
Scamarcio
, N.
Hoyler
, and J.
Faist
, “Influence of InAs, AlAs δ layers on the optical, electronic, and thermal characteristics of strain-compensated GaInAs/AlInAs quantum-cascade lasers
,” Appl. Phys. Lett.
91
(16
), 161111
(2007
).19.
C. A.
Evans
, V. D.
Jovanovic
, D.
Indjin
, Z.
Ikonic
, and P.
Harrison
, “Investigation of thermal effects in quantum-cascade lasers
,” IEEE J. Quantum Electron.
42
(9
), 859
–867
(2006
).20.
M. S.
Vitiello
, G.
Scamarcio
, and V.
Spagnolo
, “Time-resolved measurement of the local lattice temperature in terahertz quantum cascade lasers
,” Appl. Phys. Lett.
92
, 101116
(2008
).21.
M. S.
Vitiello
, L.
Consolino
, S.
Bartalini
, A.
Taschin
, A.
Tredicucci
, M.
Inguscio
, and P.
De Natale
, “Quantum-limited frequency fluctuations in a terahertz laser
,” Nature Photon.
6
, 525
–528
(2012
).22.
J.
Buus
, M. C.
Amann
, and D. J.
Blumenthal
, Tunable Laser Diodes and Related Optical Sources
(Wiley-Interscience
, New York
, 2005
), pp. 79
–106
.23.
S.
Adachi
, Physical Properties of III–V Semiconductor Compounds: InP, InAs, GaAs, GaP, InGaAs, and InGaAsP
(Wiley
, New York
, 1992
).24.
S. T.
Huxtable
, A.
Shakouri
, C.
LaBounty
, X.
Fan
, P.
Abraham
, Y. J.
Chiu
, and A.
Majumdar
, “Thermal conductivity of indium phosphide-based superlattices
,” Microscale Thermophys. Eng.
4
(3
), 197
–203
(2000
).25.
S.
Borri
, S.
Bartalini
, P.
De Natale
, M.
Inguscio
, C.
Gmachl
, F.
Capasso
, D. L.
Sivco
, and A. Y.
Cho
, “Frequency modulation spectroscopy by means of quantum-cascade lasers
,” Appl. Phys. B
85
, 223
–229
(2006
).© 2013 AIP Publishing LLC.
2013
AIP Publishing LLC
You do not currently have access to this content.