Greatly enhanced continuous-wave terahertz emission by nano-electrodes in a photoconductive photomixer

Narrowband terahertz emitters using metamaterial films

“…For example, FELs generate high power at the expense of requiring a large footprint while the QCLs are compact but only operate at cryogenic temperatures. More recent attempts on THz generation at room temperature include the use of resonant tunneling diode based oscillators [12] and nano-electrodes in a photoconductive photomixer [13], where the generated power levels are still in the microwatt range. An alternative approach to generate THz is to use a heated object with its emissivity tailored to match the specific THz frequency band of interest.…”

Considerations for surface reconstruction stability prediction on GaAs(001)

“…2,4 The high charge mobility and very low carrier lifetime in defected LTG GaAs make it particularly well suited for THz-range heterodyne photomixers. 5,6 The low-temperature growth regime is also used to enhance incorporation in low-solubility alloy systems, such as Ga 1−x Bi x As 7 and the ferroelectric semiconductor Ga 1−x Mn x As 8 Significant theoretical study of GaAs(001) has previously identified only two stable As-rich surface reconstructions, relative to bulk stoichiometry: the c(4×4) and β2(2×4), illustrated in Figs. 1(a) and 1(b), respectively.…”

Terahertz emission mechanism and laser excitation position dependence of nano-grating electrode photomixers

“…HERE have been several reports of enhanced THz emission from photomixers incorporating nanostructured electrodes both in pulsed [1] and CW operation [2,3]. In particular, plasmonic nanostructure emitters based on NSGs have been reported to result in better optical coupling to the semiconductor substrate as well as decreased carrier transit times (and therefore lifetimes) owing to the excitation of surface plasmons [1] bound to the metal-semiconductor interface.…”