Journal: Sensors (Basel, Switzerland)

Article Title: Subwavelength Diffractive Optical Elements for Generation of Terahertz Coherent Beams with Pre-Given Polarization State.

doi: 10.3390/s23031579

Figure Lengend Snippet: Figure 1. Fast (black) and slow (orange) axis of the subwavelength gratings for generation of different order (n = 1, 2, 3) cylindrical vector beams.

Article Snippet: Citation: Pavelyev, V.; Khonina, S.; Degtyarev, S.; Tukmakov, K.; Reshetnikov, A.; Gerasimov, V.; Osintseva, N.; Knyazev, B. Subwavelength Diffractive Optical Elements for Generation of Terahertz Coherent Beams with Pre-Given Polarization State.

Techniques: Plasmid Preparation

Journal: Sensors (Basel, Switzerland)

Article Title: Subwavelength Diffractive Optical Elements for Generation of Terahertz Coherent Beams with Pre-Given Polarization State.

doi: 10.3390/s23031579

Figure Lengend Snippet: Figure 3 shows the dependence of maxima values of the x-component of the horizontal and vertical pairs, as well as the values of the maximum of the y-component on the height of the relief of the subwavelength grating. The amplitudes shown in Figure 3 have absolute values and are not normalized. According to the dynamics of these graphs, it can be seen that initially, most of the energy is contained in the X-component. This is expected because the original field is X-polarized. Increasing the height of the relief to 37 microns allows us to slightly increase the energy in the Y-component by reducing it in the X-component. However, this leaves an asymmetry in the structure of the X-components (see the first row of Table 1). Therefore, we considered a further increase in the relief height to 50 microns, where, firstly, the intersection of three graphs is observed, and, secondly, a symmetrical structure in both transverse components (see the second row of Table 1). We believe that this situation corresponds to the formation of a second-order radial polarization. Unfortunately, in this case, a significant part of the energy is lost, which is scattered on a diffraction structure with high relief.

Article Snippet: Citation: Pavelyev, V.; Khonina, S.; Degtyarev, S.; Tukmakov, K.; Reshetnikov, A.; Gerasimov, V.; Osintseva, N.; Knyazev, B. Subwavelength Diffractive Optical Elements for Generation of Terahertz Coherent Beams with Pre-Given Polarization State.

Techniques:

Journal: Sensors (Basel, Switzerland)

Article Title: Subwavelength Diffractive Optical Elements for Generation of Terahertz Coherent Beams with Pre-Given Polarization State.

doi: 10.3390/s23031579

Figure Lengend Snippet: Figure 3. Dependence of the values of the maxima of the x-component of the horizontal (red line) and vertical (black line) pairs, as well as the values of the maximum of the y-component (blue line) on the elevation of the subwavelength grating.

Article Snippet: Citation: Pavelyev, V.; Khonina, S.; Degtyarev, S.; Tukmakov, K.; Reshetnikov, A.; Gerasimov, V.; Osintseva, N.; Knyazev, B. Subwavelength Diffractive Optical Elements for Generation of Terahertz Coherent Beams with Pre-Given Polarization State.

Techniques:

Journal: Sensors (Basel, Switzerland)

Article Title: Subwavelength Diffractive Optical Elements for Generation of Terahertz Coherent Beams with Pre-Given Polarization State.

doi: 10.3390/s23031579

Figure Lengend Snippet: Figure 4. Central zones of subwavelength elements (a–c) and expected distributions of local polarization (d–f). Radiation polarized along x-axis is incident on elements normally to the plane of the figure.

Article Snippet: Citation: Pavelyev, V.; Khonina, S.; Degtyarev, S.; Tukmakov, K.; Reshetnikov, A.; Gerasimov, V.; Osintseva, N.; Knyazev, B. Subwavelength Diffractive Optical Elements for Generation of Terahertz Coherent Beams with Pre-Given Polarization State.

Techniques:

Journal: Sensors (Basel, Switzerland)

Article Title: Subwavelength Diffractive Optical Elements for Generation of Terahertz Coherent Beams with Pre-Given Polarization State.

doi: 10.3390/s23031579

Figure Lengend Snippet: Figure 3 shows that the three lines intersect at a relief height of 50 microns. We will choose this height for the following manufacturing of the element. The subwavelength elements have been designed by methods based on the rigorous light theory [64]. The following DOE parameters were chosen: the aperture diameter D = 50 mm, discretization step s = 10 µm, and wavelength λ = 141 µm. Figure 4a–c shows the calculated binary subwavelength microrelief of meta-axicons for generating terahertz beams with radial polarization of the first, second, and third orders, respectively. Also, the meta-axicons add a focusing phase to the beam (NA = 0.3). In neighboring ring- shaped Fresnel zones, subwavelength grating ridges are perpendicular to each other that provide a focusing phase in the output beam. Figure 4d–f presents the pre-given transverse distribution of the beams (red color for horizontal polarization and green color for vertical polarization).

Article Snippet: Citation: Pavelyev, V.; Khonina, S.; Degtyarev, S.; Tukmakov, K.; Reshetnikov, A.; Gerasimov, V.; Osintseva, N.; Knyazev, B. Subwavelength Diffractive Optical Elements for Generation of Terahertz Coherent Beams with Pre-Given Polarization State.

Techniques:

Journal: Sensors (Basel, Switzerland)

Article Title: Subwavelength Diffractive Optical Elements for Generation of Terahertz Coherent Beams with Pre-Given Polarization State.

doi: 10.3390/s23031579

Figure Lengend Snippet: Figure 5. Calculated amplitude distributions at a distance of 5 wavelengths from the plane of the subwavelength elements with different polarization orders: for MAx1 (a), MAx2 (b), and MAx3 (c).

Article Snippet: Citation: Pavelyev, V.; Khonina, S.; Degtyarev, S.; Tukmakov, K.; Reshetnikov, A.; Gerasimov, V.; Osintseva, N.; Knyazev, B. Subwavelength Diffractive Optical Elements for Generation of Terahertz Coherent Beams with Pre-Given Polarization State.

Techniques: