A Broad-Band Achromatic Polarization-Insensitive In-Plane Lens with High Focusing Efficiency

Atalay, Ipek Anil; Yilmaz, Yusuf Abdulaziz; Savas, Firat Cem; Kurt, Hamza

doi:10.1021/acsphotonics.1c00721

Cited by 7 publications

(2 citation statements)

References 34 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Inverse design is an approach which iteratively operates to find the optimum structure to obtain the desired electromagnetic behavior according to the predefined objective [29,30]. Proposed optical logic gates in this study are designed with the 'objective-first algorithm' (OB-1) [31] which is a wellknown solution method used in various nanophotonic designs such as in-plane lens [32], optical diode [33], wavelength demultiplexers [34] and mode converters [35]. In OB-1 algorithm, objective parameters for the desired nanophotonic device are entered inside the cost function.…”

Section: Structural Parameters and Inverse Design Concept Of Optical ...mentioning

confidence: 99%

Inverse design of ultra-compact photonic gates for all-optical logic operations

Neşeli¹,

Yilmaz²,

Kurt³

et al. 2022

J. Phys. D: Appl. Phys.

Self Cite

View full text Add to dashboard Cite

Logic gates have great importance in realization of rapid data transmission as well as low loss transfers. In this paper, a multi-objective inverse-design approach is implemented by using objective-first algorithm to design optical AND, OR, NAND and NOT logic gates on Si- platform at the design wavelength of 1.30 μm. For all gates, the design area is fixed to 2.24 μm × 2.24 μm. The optical logic “1” output is accepted to be optical power values greater than 0.8 times of the input optical power. By implementing a Bias waveguide as well as two input ports, we made it possible to achieve logic “1” output for logic operations having no inputs such as “0 NAND 0 = 1” and “0 NOT = 1”. We binarized the proposed logic gates, and then numerically analyzed them by using finite-difference time-domain (FDTD) method. Proposed AND gate yields 1.20 times of input power for “1 AND 1 = 1” logic operation and highest logic “0” is obtained for logic operation of “1 AND 0 = 0” as 0.40 times of the input power at the operating wavelength. It is also observed that proposed logic gates can operate not only at the design wavelength of 1.30 μm but also at broad wavelength regions as well. Finally, we demonstrate that it is possible to carry out complex logic operations by combining the proposed logic AND, OR and NAND gates to construct an XOR gate in the same platform.

show abstract

Section: Structural Parameters and Inverse Design Concept Of Optical ...mentioning

confidence: 99%

Inverse design of ultra-compact photonic gates for all-optical logic operations

Neşeli¹,

Yilmaz²,

Kurt³

et al. 2022

J. Phys. D: Appl. Phys.

Self Cite

View full text Add to dashboard Cite

show abstract

“…In the terahertz (THz) and optical regimes, dielectric metalenses have been proposed to achieve efficient control of different EM polarizations. [ 10,38–45 ] However, due to the resonant nature of the dielectric unit cells, the dielectric metalenses usually have narrow operation bands.…”

Section: Introductionmentioning

confidence: 99%

Broadband Terahertz Metalenses Based on Printed Circuit Board Fabrication

Qi,

He,

Ren

et al. 2024

Advanced Optical Materials

View full text Add to dashboard Cite

Metalenses have provided a good solution to the bulkiness of conventional refractive lenses. Due to the subwavelength feature sizes of the metalens structure, the increasing fabrication difficulties at high frequencies limit its application in the terahertz and optical regime. Moreover, the deeply subwavelength features of the metasurface unit cells usually make the cells strongly resonant, which limits the bandwidth of the metalens. In this paper the usage of aggressive discretization in a metalens design is investigated, and it is found that aggressive discretization can lead to the usage of weakly resonant and relatively large unit cells, which leads to excellent broadband performance and dramatically relaxes the feature size tolerance of the metalens. For examples, two terahertz focusing metalenses are designed which feature large numerical apertures (NA = 0.86), diffraction‐limited focusing over a broad bandwidth (240–400 GHz, or 50% bandwidth), and minimum feature sizes of 0.1 mm. These tolerance‐relaxed terahertz metalenses are successfully constructed using conventional printed‐circuit‐board fabrication technology. The experimental measurements validate the simulated performances. Compared to existing terahertz meta‐devices based on micro‐fabrication or nano‐fabrication technologies, this paper opens door to a kind of high‐quality terahertz metasurfaces featuring low‐cost, rapid, and established fabrication.

show abstract