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Title: Continuous wave operation of terahertz metasurface quantum-cascade VECSEL with a long intra-cryostat cavity
We report continuous wave (cw) operation of a terahertz quantum-cascade vertical-external-cavity surface-emitting laser with an external cavity length of approximately 30 mm, benefited by an intra-cryostat focusing cavity. Compared to previous plano–plano cavities, an off-axis paraboloid mirror is introduced into the external cavity as a focusing element to reduce the diffraction loss and to enable cw lasing using small-area metasurfaces and long cavity lengths. The device shows lasing operation in the cw mode up to 111 K, and cw output power up to 11.5 mW at 77 K (0.5% wall-plug efficiency). A circular, directive beam pattern is collected, and free-running linewidths on the order of tens of kHz are measured over tens of seconds.  more » « less
Award ID(s):
2041165
NSF-PAR ID:
10398683
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Applied Physics Letters
Volume:
121
Issue:
19
ISSN:
0003-6951
Page Range / eLocation ID:
191106
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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