Resonance modes in coplanar lines with integrated Josephson circuits

Magnetoelectric resonators have been studied for the detection of small amplitude and low frequency magnetic fields via the delta-E effect, mainly in fundamental bending or bulk resonance modes. Here, we present an experimental and theoretical investigation of magnetoelectric thin-film cantilevers that can be operated in bending modes (BMs) and torsion modes (TMs) as a magnetic field sensor. A magnetoelastic macrospin model is combined with an electromechanical finite element model and a general description of the delta-E effect of all stiffness tensor components Cij is derived. Simulations confirm quantitatively that the delta-E effect of the C66 component has the promising potential of significantly increasing the magnetic sensitivity and the maximum normalized frequency change ∆fr. However, the electrical excitation of TMs remains challenging and is found to significantly diminish the gain in sensitivity. Experiments reveal the dependency of the sensitivity and ∆fr of TMs on the mode number, which differs fundamentally from BMs and is well explained by our model. Because the contribution of C11 to the TMs increases with the mode number, the first-order TM yields the highest magnetic sensitivity. Overall, general insights are gained for the design of high-sensitivity delta-E effect sensors, as well as for frequency tunable devices based on the delta-E effect.

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Nonlinear oscillations produced in complex Josephson circuits

1991., IEEE International Sympoisum on Circuits and Systems ◽

10.1109/iscas.1991.176172 ◽

2002 ◽

Author(s):

M. Morisue ◽

J. Gu ◽

T. Morimae ◽

M. Otake

Keyword(s):

Nonlinear Oscillations ◽

Josephson Circuits

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Weyl Josephson circuits

Physical Review Research ◽

10.1103/physrevresearch.3.013288 ◽

2021 ◽

Vol 3 (1) ◽

Author(s):

Valla Fatemi ◽

Anton R. Akhmerov ◽

Landry Bretheau

Keyword(s):

Josephson Circuits

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Design of a Liquid-Crystal-Tunable Terahertz Demultiplexer Based on a Metal-Insulator-Metal Waveguide

Applied Sciences ◽

10.3390/app9040644 ◽

2019 ◽

Vol 9 (4) ◽

pp. 644

Author(s):

Xue-Shi Li ◽

Naixing Feng ◽

Yuan-Mei Xu ◽

Liang-Lun Cheng ◽

Qing Liu

Keyword(s):

Liquid Crystal ◽

Electric Field ◽

Metal Insulator ◽

Resonance Modes ◽

External Bias ◽

Bias Electric Field ◽

Metal Waveguide ◽

Metal Insulator Metal ◽

Fabry Perot ◽

Mim Waveguide

A tunable demultiplexer with three output channels infiltrated by liquid crystal (LC) is presented, which is based on a metal-insulator-metal (MIM) waveguide. The operating frequencies of the three output channels can be tuned simultaneously at will by changing the external bias electric field applied to the LC. By analyzing the Fabry-Pérot (FP) resonance modes of the finite-length MIM waveguide both theoretically and numerically, the locations of the three channels are delicately determined to achieve the best demultiplexing effects. Terahertz (THz) signals input from the main channel can be demultiplexed by channels 1, 2 and 3 at 0.7135 THz, 1.068 THz and 1.429 THz, respectively. By applying an external electric field to alter the tilt angle of the infiltrating LC material, the operating frequencies of channels 1, 2 and 3 can be relatively shifted up to 12.3%, 9.6% and 9.7%, respectively. The designed demultiplexer can not only provide a flexible means to demultiplex signals but also tune operating bands of output channels at the same time.

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Adiabatic mode transformation in width-graded nano-gratings enabling multiwavelength light localization

Scientific Reports ◽

10.1038/s41598-020-79815-9 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Moein Shayegannia ◽

Arthur O. Montazeri ◽

Katelyn Dixon ◽

Rajiv Prinja ◽

Nastaran Kazemi-Zanjani ◽

...

Keyword(s):

Multispectral Imaging ◽

Groove Depth ◽

Surface Enhanced Raman Spectroscopy ◽

Fine Tuning ◽

Mode Transformation ◽

Resonance Modes ◽

Light Localization ◽

Metal Insulator Metal ◽

Surface Enhanced Raman ◽

Adiabatic Mode

AbstractWe delineate the four principal surface plasmon polariton coupling and interaction mechanisms in subwavelength gratings, and demonstrate their significant roles in shaping the optical response of plasmonic gratings. Within the framework of width-graded metal–insulator-metal nano-gratings, electromagnetic field confinement and wave guiding result in multiwavelength light localization provided conditions of adiabatic mode transformation are satisfied. The field is enhanced further through fine tuning of the groove-width (w), groove-depth (L) and groove-to-groove-separation (d). By juxtaposing the resonance modes of width-graded and non-graded gratings and defining the adiabaticity condition, we demonstrate the criticality of w and d in achieving adiabatic mode transformation among the grooves. We observe that the resonant wavelength of a graded grating corresponds to the properties of a single groove when the grooves are adiabatically coupled. We show that L plays an important function in defining the span of localized wavelengths. Specifically, we show that multiwavelength resonant modes with intensity enhancement exceeding three orders of magnitude are possible with w < 30 nm and 300 nm < d < 900 nm for a range of fixed values of L. This study presents a novel paradigm of deep-subwavelength adiabatically-coupled width-graded gratings—illustrating its versatility in design, hence its viability for applications ranging from surface enhanced Raman spectroscopy to multispectral imaging.

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