Journal ArticleDOI
Phase-Shifted Fresnel Zone Lenses for Photomixing Generation of Coherent THz Wave
TLDR
In this article, phase-shifted Fresnel zone lenses (FZLs) were used for THz wave generation by mixing optical beams from integrated twin lasers on GaAs photomixers.Abstract:
Novel optics configurations simplified by using phase-shifted Fresnel zone lenses (FZLs) are proposed for THz wave generation by mixing optical beams from integrated twin lasers on GaAs photomixers. The phase-shifted FZL superimposes and collinearly collimates the beams from the closely-aligned twin lasers, or superimposes and focuses them directly onto a photomixer, with a high efficiency. Phase-shifted binary and analog FZLs were designed and fabricated by electron beam writing. Good performances close to the theoretical prediction were obtained, and THz wave generation was successfully demonstrated.read more
Citations
More filters
Journal ArticleDOI
Experimental demonstration of square Fresnel zone plate with chiral side lobes.
TL;DR: The CSFZP beam pattern was implemented in an optical trapping experiment and was found to possess particle trapping capabilities, with a strong central focal spot and twisted side lobes.
Journal ArticleDOI
Characterization and correction of spherical aberration due to glass substrate in the design and fabrication of Fresnel zone lenses
TL;DR: Two novel schemes for correction of spherical aberration are proposed and studied and the accuracy of the proposed aberration correction schemes is validated.
Journal ArticleDOI
Quasi-achromatic Fresnel zone lens with ring focus.
TL;DR: Experimental results confirm the generation of a wavelength-independent ring pattern at the focus of the rf-FZL, which is found to be quasi-achromatic, in that the diameter is wavelength independent but its location is not.
Journal ArticleDOI
Binary square axicon with chiral focusing properties for optical trapping
B. Vinoth,Anand Vijayakumar,Anand Vijayakumar,Mani Ratnam Rai,Joseph Rosen,Chau Jern Cheng,Oleg V. Minin,Oleg V. Minin,Igor V. Minin,Igor V. Minin +9 more
TL;DR: In this article, a phase-only diffractive optical element called chiral binary square axicon (CBSA) is introduced, which is designed by linearly rotating the square half-period zones of the binary squares axicon with respect to one another.
References
More filters
Journal ArticleDOI
Generation and detection of coherent terahertz waves using two photomixers
TL;DR: In this article, a general technique has been demonstrated at microwave and submillimeter-wave frequencies for photoconductive sampling in the frequency domain using photomixers and continuous-wave laser diodes.
Journal ArticleDOI
Generation of coherent terahertz radiation by photomixing in dipole photoconductive antennas
TL;DR: In this article, the authors demonstrate the generation of continuous-wave terahertz radiation at frequencies up to 3.5 THz by photomixing in LT-GaAs photoconductors with printed dipole antennas.
Journal ArticleDOI
Blazed gratings and Fresnel lenses fabricated by electron-beam lithography
TL;DR: A blazing technique using electron-beam lithography to achieve higher efficiency of gratings and Fresnel lenses is described, and the experimental results showed high-efficiency performance and nearly diffraction-limited focusing.
Journal ArticleDOI
Fabrication of micro lenses using electron-beam lithography
TL;DR: It was found that ordinary-type Fresnel (zone-plate) lenses and a special-type lens for converting an incident Gaussian intensity distribution into a uniform one have near-diffraction-limited performance.
Journal ArticleDOI
Laser beam lithographed micro-Fresnel lenses
TL;DR: Laser beam lithography for micro-Fresnel lenses (MFLs) with blazed grooves is proposed and demonstrated including the system configuration and characteristics of the resulting lenses, with nearly diffraction-limited spot sizes obtained with diffraction efficiencies of 50% or more.
Related Papers (5)
Terahertz generation in quasi-phase-matching structure formed by a phase mask
Terahertz beam steering and frequency tuning by using the spatial dispersion of ultrafast laser pulses.
Ken-ichiro Maki,Chiko Otani +1 more