Transformation of the multimode terahertz quantum cascade laser beam into a Gaussian, using a hollow dielectric waveguide.
We demonstrate that a short hollow dielectric tube can act as a dielectric waveguide and transform the multimode, highly diverging terahertz quantum cascade laser beam into the lowest order dielectric waveguide hybrid mode, EH(11), which then couples efficiently to the free-space Gaussian mode, TEM(00). This simple approach should enable terahertz quantum cascade lasers to be employed in applications where a spatially coherent beam is required.
Submillimeter-Wave Technology Laboratory, University of Massachusetts Lowell, Lowell, Massachusetts 01854, USA. andriy_danylov@student.uml.edu
Andriy A
AA
Danylov
Jerry
J
Waldman
Thomas M
TM
Goyette
Andrew J
AJ
Gatesman
Robert H
RH
Giles
Kurt J
KJ
Linden
William R
WR
Neal
William E
WE
Nixon
Michael C
MC
Wanke
John L
JL
Reno