Transmission of single-cycle terahertz pulses through subwavelength apertures is experimentally studied in the near-field zone. Measurements of throughput for aperture sizes d as small as λ/300 show that the theoretical d3 law requires a correction term which takes into account the physical thickness of the aperture screen. Frequency dependent transmission of the broad band pulses explains changes in their spectral and temporal characteristics. Practical application of small apertures in near-field microscope probes allows achievement of spatial resolution of 7 μm for pulses with a broad spectral content of λ = 120-1500 μm.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy (miscellaneous)