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We present systematic experimental studies of the impact of subwavelength structural geometries and electromagnetic field polarization on the resonance behavior of metallic metasurfaces at D-band frequencies. The measured influence of the photoconductive receiver antenna design in terahertz time-domain spectroscopy on the frequency-domain spectral features was analyzed. Numerical simulations reveal distinct resonance characteristics in the D-band regime, where extraordinary amplitude transmission is highly dependent on the array dimensions and field polarization orientation. The metasurface enables significant enhancements in surface electric fields and resonance response, attributed to the effective excitation of strong dipolar modes. These results demonstrate the extraordinary transmission capabilities of subwavelength metallic arrays and provide valuable insights for designing compact, low-loss, and tunable terahertz functional components needed in next-generation communications.
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This content will become publicly available on January 1, 2027
Time‐Domain Near‐Field Scanning Microscopy of Terahertz Metasurfaces
Metasurfaces have emerged as an ultrathin, versatile method for manipulating terahertz surface plasma waves that are critical for subwavelength optical control but are very challenging to be excited and characterized. This review presents recent advances in terahertz surface plasmon waves, focusing on three functional areas: excitation through resonant coupling, beam shaping through phase gradient design, and complex field encoding using metaholography. To validate and analyze these phenomena, near‐field scanning terahertz microscopy (NSTM) is recently developed as a powerful tool for mapping the field distribution of surface plasmon waves, spin‐ and polarization‐sensitive responses, and vector wavefront structures with subwavelength resolution. Representative metasurfaces architectures are highlighted, including periodic and nonperiodic resonators, dynamic phase modulators, and multiplexed holographic encoders, and summarize how their performance can be directly observed through the NSTM platform. Together, these studies demonstrate the synergy between metasurfaces design and near‐field characterization. The integration of reconfigurable metasurfaces with an advanced near‐field scanning platform will be key to realizing high‐capacity, tunable terahertz photonic devices.
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- PAR ID:
- 10698805
- Publisher / Repository:
- Wiley-VCH GmbH
- Date Published:
- Journal Name:
- Advanced Photonics Research
- Volume:
- 7
- Issue:
- 1
- ISSN:
- 2699-9293
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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