Wei Jie Gao

My research interest focuses on terahertz waveguides, components, antennas, and microwave reconfigurable antennas. Research in terahertz integrated systems as a frontier of photonics have attracted a great attention. With integrability, portability, and low cost, terahertz integrated systems promise a wide range of unique applications, from 6G wireless communications to nondestructive imaging. To this end, terahertz integrated waveguide platforms with high efficiency, low dispersion, and broad bandwidth are crucial to build the comprehensive systems. Up until recent years, there was no unique integrated platform for terahertz systems available. Existing platforms adopted either millimeter-wave or photonic integrated circuit into the terahertz range. However, all those adopted platforms exhibit limitations in this range in terms of efficiency and bandwidth. Recently, we have proposed a class of self-supporting substrate-free effective-medium-clad dielectric waveguides together with a series of elementary components as building blocks for a terahertz integrated platform at WR-3 band. Based on the proposed platform, I have developed several terahertz components including effective-medium-clad Bragg grating filters, effective-medium-based lens antenna, and terahertz polarization beam splitter. All these devices feature high efficiency with a fractional bandwidth of 40%. We can foresee that the concept of effective medium can benefit integrated photonics at large.