CM-AMO Seminar | Plasmonic Photoconductive Terahertz Radiation Sources

Speaker: Mona Jarrahi (U-M)

Although the unique potentials of terahertz waves for chemical identification, material characterization, biological sensing and medical imaging has been known for quite a while, low output power, low efficiency, high cost, and bulky nature of current terahertz sources continue to hinder practical feasibility of such applications. One of the most promising terahertz generation schemes is based on photoconductive photomixing. Photomixers are known to offer excellent frequency tunability and high spectral purity at room temperature, but their shortcoming is low output power, which is ultimately limited by thermal breakdown at high pump power levels. To address the output power limitations of existing photomixers, we present a new generation of plasmonic photomixers pumped at telecom pump wavelengths at which very high power, narrow linewidth, wavelength-tunable, compact and cost-efficient optical sources are available. By tackling the major obstacle of thermal breakdown of conventional photomixers, the proposed technology is expected to offer terahertz power levels that are orders of magnitude higher than is currently available from existing technologies.