Phase-sensitive terahertz imaging using room-temperature near-field nanodetectors

Maria C. Giordano; Leonardo Viti; Oleg Mitrofanov; Miriam S. Vitiello

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arXiv · 1903.06200

Phase-sensitive terahertz imaging using room-temperature near-field nanodetectors

Maria C. Giordano·Leonardo Viti·Oleg Mitrofanov·Miriam S. Vitiello

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Abstract

Imaging applications in the terahertz (THz) frequency range are severely restricted by diffraction. Near-field scanning probe microscopy is commonly employed to enable mapping of the THz electromagnetic fields with sub-wavelength spatial resolution, allowing intriguing scientific phenomena to be explored such as charge carrier dynamics in nanostructures and THz plasmon-polaritons in novel 2D materials and devices. High-resolution THz imaging, so far, has been relying predominantly on THz detection techniques that require either an ultrafast laser or a cryogenically-cooled THz detector. Here, we demonstrate coherent near-field imaging in the THz frequency range using a room-temperature nanodetector embedded in the aperture of a near-field probe, and an interferometric optical setup driven by a THz quantum cascade laser (QCL). By performing phase-sensitive imaging of strongly confined THz fields created by plasmonic focusing we demonstrate the potential of our novel architecture for high-sensitivity coherent THz imaging with sub-wavelength spatial resolution.

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Maria C. Giordano, Leonardo Viti, Oleg Mitrofanov, Miriam S. Vitiello. 2019-03-14. Phase-sensitive terahertz imaging using room-temperature near-field nanodetectors. https://arxiv.org/abs/1903.06200

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