Spatial Sampling of Terahertz Fields with Sub-wavelength Accuracy via Probe Beam Encoding

Abstract

Recently, computational sampling methods have been implemented to spatially characterize terahertz (THz) fields. Previous methods usually rely on either specialized THz devices such as THz spatial light modulators, or complicated systems requiring assistance from photon-excited free-carriers with high-speed synchronization among multiple optical beams. Here, by spatially encoding an 800 nm near-infrared (NIR) probe beam through the use of an optical SLM, we demonstrate a simple sampling approach that can probe THz fields with a single-pixel camera. This design does not require any dedicated THz devices, semiconductors or nanofilms to modulate THz fields. Through the use of computational algorithms, we successfully measure 128$\times$128 field distributions with a 62 $\mu m$ transverse spatial resolution, more than 15 times smaller than the central wavelength of the THz signal (940 $\mu m$). Benefitting from the non-invasive nature of THz radiation and sub-wavelength resolution of our system, this simple approach can be used in applications such as biomedical sensing, inspection of flaws. in industrial products, and so on.

arXiv commentMain manuscript: 7 pages, 3 figures; Supplement: 8 pages, 3 figures;

References in corpus (3)

• Efficient metallic spintronic emitters of ultrabroadband terahertz radiation
• Non-invasive, near-field terahertz imaging of hidden objects using a single pixel detector
• Ultrafast single-nanowire multi-terahertz spectroscopy with sub-cycle temporal resolution

Cited by in corpus (11)

• Hyperspectral terahertz microscopy via nonlinear ghost imaging
• Mid-infrared single-pixel imaging at the single-photon level
• Rapid Sensing of Hidden Objects and Defects using a Single-Pixel Diffractive Terahertz Processor
• Plasmonic photoconductive terahertz focal-plane array with pixel super-resolution
• Ultrafast pulse measurement via time-domain single-pixel imaging
• Self-evolving ghost imaging
• Deterministic Terahertz wave control in scattering media
• Fourier Synthetic Aperture-based Time-resolved Terahertz Imaging
• Deep Learning Empowered Sub-Diffraction Terahertz Backpropagation Single-Pixel Imaging
• Multi-wavelength ghost imaging: a review
• Ghost spintronic THz-emitter-array microscope