The Experts below are selected from a list of 249 Experts worldwide ranked by ideXlab platform
John R Clem - One of the best experts on this subject based on the ideXlab platform.
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Inductances and Attenuation Constant for a thin-film superconducting coplanar waveguide resonator
Journal of Applied Physics, 2013Co-Authors: John R ClemAbstract:The geometric, kinetic, and total inductances and the Attenuation Constant are theoretically analyzed for a thin-film superconducting coplanar waveguide resonator consisting of a current-carrying central conductor, adjacent slots, and ground planes that return the current. The analysis focuses on films of thickness d obeying d
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inductances and Attenuation Constant for a thin film superconducting coplanar waveguide resonator
arXiv: Superconductivity, 2012Co-Authors: John R ClemAbstract:The geometric, kinetic, and total inductances and the Attenuation Constant are theoretically analyzed for a thin-film superconducting coplanar waveguide (CPW) resonator consisting of a current-carrying central conductor, adjacent slots, and ground planes that return the current. The analysis focuses on films of thickness $d$ obeying $d < 2\lambda$ ($\lambda$ is the London penetration depth), for which the material properties are characterized by the two-dimensional screening length $\Lambda = 2 \lambda^2/d$. Introducing a cut-off procedure that guarantees that the magnitudes of the currents in the central conductor and the ground planes are equal, new and simpler results are obtained for the kinetic inductance and the Attenuation Constant for small $\Lambda$. Exact results for arbitrary $\Lambda$ are presented for the geometric, kinetic, and total inductances in the limit of tiny slot widths, and approximate results are presented for arbitrary slot widths.
C.l. Holloway - One of the best experts on this subject based on the ideXlab platform.
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Conductor loss in superconducting planar structures: calculations and measurements
IEEE Transactions on Microwave Theory and Techniques, 1999Co-Authors: J.c. Booth, C.l. HollowayAbstract:We present closed-form expressions of the Attenuation Constant due to conductor loss for superconducting coplanar waveguide and microstrip transmission lines. These expressions, valid for arbitrary conductor thickness, make use of a numerically determined quantity (the stopping distance /spl Delta/) that depends on the material properties and edge shape of the superconducting transmission line. Once /spl Delta/ is determined, the Attenuation Constant for any planar geometry can be obtained without further numerical calculation, making this technique attractive for use in the design of circuits incorporating superconducting planar elements. The results of this calculation compare favorably with full numerical calculations and also with experimental data on high-temperature superconducting coplanar transmission lines, illustrating the accuracy and applicability of the calculation for determining the conductor loss of superconducting circuit elements.
J.c. Booth - One of the best experts on this subject based on the ideXlab platform.
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Conductor loss in superconducting planar structures: calculations and measurements
IEEE Transactions on Microwave Theory and Techniques, 1999Co-Authors: J.c. Booth, C.l. HollowayAbstract:We present closed-form expressions of the Attenuation Constant due to conductor loss for superconducting coplanar waveguide and microstrip transmission lines. These expressions, valid for arbitrary conductor thickness, make use of a numerically determined quantity (the stopping distance /spl Delta/) that depends on the material properties and edge shape of the superconducting transmission line. Once /spl Delta/ is determined, the Attenuation Constant for any planar geometry can be obtained without further numerical calculation, making this technique attractive for use in the design of circuits incorporating superconducting planar elements. The results of this calculation compare favorably with full numerical calculations and also with experimental data on high-temperature superconducting coplanar transmission lines, illustrating the accuracy and applicability of the calculation for determining the conductor loss of superconducting circuit elements.
Chi-kuang Sun - One of the best experts on this subject based on the ideXlab platform.
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Subwavelength plastic fiber for terahertz wave guiding
Terahertz Physics Devices and Systems, 2006Co-Authors: Chi-kuang Sun, Li-jin Chen, Hung-wen ChenAbstract:We report a simple subwavelength-diameter plastic wire, similar to an optical fiber, for guiding terahertz wave with a low Attenuation Constant. With a large wavelength-to-fiber-core ratio, the fractional power delivered inside the lossy core is reduced, thus lowering the effective fiber Attenuation Constant. In our experiment, we adopt a polyethylene fiber with a 200-500 μm diameter for guiding terahertz waves in the frequency range of 0.2-0.5 THz in which the Attenuation Constant is reduced to the order of or less than 0.01 cm -1 . Direct free-space coupling efficiency, as high as 20%, can be achieved by using an off-axis parabolic mirror. Furthermore, all the plastic wires are easily available in our daily life without complex processes and expensive costs.
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low loss subwavelength plastic fiber for terahertz waveguiding
Optics Letters, 2006Co-Authors: Li-jin Chen, Hung-wen Chen, Tzengfu Kao, Chi-kuang SunAbstract:We report a simple subwavelength-diameter plastic wire, similar to an optical fiber, for guiding a terahertz wave with a low Attenuation Constant. With a large wavelength-to-fiber-core ratio, the fractional power delivered inside the lossy core is reduced, thus lowering the effective fiber Attenuation Constant. In our experiment we adopt a polyethylene fiber with a 200 µm diameter for guiding terahertz waves in the frequency range near 0.3 THz in which the Attenuation Constant is reduced to of the order of or less than 0.01 cm−1. Direct free-space coupling efficiency as high as 20% can be achieved by use of an off-axis parabolic mirror. Furthermore, all the plastic wires are readily available, with no need for complex or expensive fabrication.
Nihar K Sahoo - One of the best experts on this subject based on the ideXlab platform.
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Attenuation Constant and characteristic impedance calculation of top metal covered cpw transmission line using neural networks
Journal of Computational Electronics, 2019Co-Authors: Amit Kumar Sahu, Dhruba C Panda, Nihar K SahooAbstract:A technique for calculating the characteristic impedance of top metal-covered coplanar waveguide (TCPW) transmission lines using a neural network is presented in this paper. Additionally, the technique is extended to calculate their Attenuation Constant. Analytical expressions based on conformal mapping techniques are not applicable when the top cover height is < 3 µm. Further, there are no analytical expressions available to calculate their Attenuation Constant. We used a feed-forward artificial neural network to calculate the characteristic impedance and Attenuation Constant of TCPWs. The results are compared with those obtained using ANSYS HFSS full-wave simulation software, which shows good agreement. This technique will be useful for equivalent circuit modeling of RF-MEMS.
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Attenuation Constant and characteristic impedance calculation of top metal-covered CPW transmission line using neural networks
Journal of Computational Electronics, 2019Co-Authors: Amit Kumar Sahu, Dhruba C Panda, Nihar K SahooAbstract:A technique for calculating the characteristic impedance of top metal-covered coplanar waveguide (TCPW) transmission lines using a neural network is presented in this paper. Additionally, the technique is extended to calculate their Attenuation Constant. Analytical expressions based on conformal mapping techniques are not applicable when the top cover height is
