title: Tunable terahertz wave generation through a bimodal laser diode and plasmonic photomixer.
abstract: We demonstrate a compact, robust, and stable terahertz source based on a novel two section digital distributed feedback laser diode and plasmonic photomixer. Terahertz wave generation is achieved through difference frequency generation by pumping the plasmonic photomixer with two output optical beams of the two section digital distributed feedback laser diode. The laser is designed to offer an adjustable terahertz frequency difference between the emitted wavelengths by varying the applied currents to the laser sections. The plasmonic photomixer is comprised of an ultrafast photoconductor with plasmonic contact electrodes integrated with a logarithmic spiral antenna. We demonstrate terahertz wave generation with 0.15-3 THz frequency tunability, 2 MHz linewidth, and less than 5 MHz frequency stability over 1 minute, at useful power levels for practical imaging and sensing applications.
authors.forename: S-H
authors.initials: SH
authors.lastname: Yang
authors.forename: R
authors.initials: R
authors.lastname: Watts
authors.forename: X
authors.initials: X
authors.lastname: Li
authors.forename: N
authors.initials: N
authors.lastname: Wang
authors.forename: V
authors.initials: V
authors.lastname: Cojocaru
authors.forename: J
authors.initials: J
authors.lastname: O'Gorman
authors.forename: L P
authors.initials: LP
authors.lastname: Barry
authors.forename: M
authors.initials: M
authors.lastname: Jarrahi
mesh_terms: D004867:Equipment Design; D019544:Equipment Failure Analysis; D054023:Lasers, Semiconductor; D008029:Lighting / Q000295:instrumentation*; D055096:Optical Devices; D012031:Refractometry / Q000295:instrumentation*; D020349:Surface Plasmon Resonance / Q000295:instrumentation*; D055069:Terahertz Imaging / Q000295:instrumentation*; D055053:Terahertz Radiation