  Improving terahertz(THz) radiation power and/or optics-to-THz efficiency of
the photoconductive antenna(PCA) is widely recognized as one of the most
attractive and challenging missions in THz community. In this work, the design
of a THz PCA with nano-crossfinger structure in the active region is proposed.
The THz radiation properties of this PCA was demonstrated by
finite-difference-time-domain method based on full-wave model. As a comparison,
the PCA with nano-finger structure that promises enhanced THz radiation than
conventional PCA was also analyzed numerically. The results indicate that the
nano-crossfinger PCA can radiate even higher THz field than the nano-finger
PCA, primarily due to the enhanced bias field within the nano-structure.
