Phase locking of a 2.7 THz quantum cascade laser to a microwave reference.
We demonstrate the phase locking of a 2.7 THz metal-metal waveguide quantum cascade laser (QCL) to an external microwave signal. The reference is the 15th harmonic, generated by a semiconductor superlattice nonlinear device, of a signal at 182 GHz, which itself is generated by a multiplier chain (x12) from a microwave synthesizer at approximately 15 GHz. Both laser and reference radiations are coupled into a bolometer mixer, resulting in a beat signal, which is fed into a phase-lock loop. The spectral analysis of the beat signal confirms that the QCL is phase locked. This result opens the possibility to extend heterodyne interferometers into the far-infrared range.
Khosropanah
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P
SRON Netherlands Institute for Space Research, Landleven 12, 9747 AD Groningen, The Netherlands.
Baryshev
A
A
Zhang
W
W
Jellema
W
W
Hovenier
J N
JN
Gao
J R
JR
Klapwijk
T M
TM
Paveliev
D G
DG
Williams
B S
BS
Kumar
S
S
Hu
Q
Q
Reno
J L
JL
Klein
B
B
Hesler
J L
JL