Phase shifter based on an ultrathin superconducting bilayer with a through-hole for a superconducting device

Abstract Applying a radian phase shift other than 2π is a key issue for superconducting circuits, such as flux qubits. The magnetic flux is useful when generating a phase shift. However, a quantized magnetic flux accompanying a trapped vortex in a superconductor does not have a phase shifter function. The magnetic flux generated by an external field generates noise. In this study, we propose a phase bias system that does not require an external field during operation. We confirm the phase shift of a direct current superconducting interference device (SQUID) placed on an ultrathin superconducting Nb bilayer with a through-hole by cooling it to a temperature below the superconducting transition temperature with an external field. Although the cause of the phase shift in our system is unclear, we believe that it may be caused by a fractional quantum in the bilayer. When the SQUID is replaced by a qubit, the phase shift can be applied to a phase bias.

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Kondo effect and superconductivity in niobium with iron impurities

Scientific Reports ◽

10.1038/s41598-021-93731-6 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Hansong Zeng ◽

Dan Zhou ◽

Guoqing Liang ◽

Rujun Tang ◽

Zhi H. Hang ◽

...

Keyword(s):

Magnetic Moment ◽

Low Temperatures ◽

Kondo Effect ◽

Film Structure ◽

Kondo Temperature ◽

Superconducting Transition ◽

Interesting Phenomenon ◽

Superconducting Device ◽

Bcc Lattice ◽

Device Applications

AbstractKondo effect is an interesting phenomenon in quantum many-body physics. Niobium (Nb) is a conventional superconductor important for many superconducting device applications. It was long thought that the Kondo effect cannot be observed in Nb because the magnetic moment of a magnetic impurity, e.g. iron (Fe), would have been quenched in Nb. Here we report an observation of the Kondo effect in a Nb thin film structure. We found that by co-annealing Nb films with Fe in Argon gas at above 400 $$^{\circ }$$ ∘ C for an hour, one can induce a Kondo effect in Nb. The Kondo effect is more pronounced at higher annealing temperature. The temperature dependence of the resistance suggests existence of remnant superconductivity at low temperatures even though the system never becomes superconducting. We find that the Hamann theory for the Kondo resistivity gives a satisfactory fitting to the result. The Hamann analysis gives a Kondo temperature for this Nb–Fe system at $$\sim $$ ∼ 16 K, well above the superconducting transition onset temperature 9 K of the starting Nb film, suggesting that the screening of the impurity spins is effective to allow Cooper pairs to form at low temperatures. We suggest that the mechanism by which the Fe impurities retain partially their magnetic moment is that they are located at the grain boundaries, not fully dissolved into the bcc lattice of Nb.

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Optical-to-RF phase shift conversion-based microwave photonic phase shifter using a fiber Bragg grating

Optics Letters ◽

10.1364/ol.39.000142 ◽

2013 ◽

Vol 39 (1) ◽

pp. 142 ◽

Cited By ~ 19

Author(s):

Xudong Wang ◽

Erwin H. W. Chan ◽

Robert A. Minasian

Keyword(s):

Phase Shift ◽

Fiber Bragg Grating ◽

Phase Shifter ◽

Bragg Grating ◽

Microwave Photonic

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A 60 GHz reconfigurable active phase shifter based on a vector modulator in 65 nm CMOS technology

International Journal of Microwave and Wireless Technologies ◽

10.1017/s1759078716000167 ◽

2016 ◽

Vol 8 (3) ◽

pp. 399-404 ◽

Cited By ~ 1

Author(s):

Boris Moret ◽

Nathalie Deltimple ◽

Eric Kerhervé ◽

Baudouin Martineau ◽

Didier Belot

Keyword(s):

Phase Shift ◽

Phase Shifter ◽

Complementary Metal Oxide Semiconductor ◽

Active Phase ◽

Cmos Technology ◽

Oxide Semiconductor ◽

60 Ghz ◽

Semiconductor Technology ◽

Vector Modulator ◽

Active Phase Shifter

This paper presents a 60 GHz reconfigurable active phase shifter based on a vector modulator implemented in 65 nm complementary metal–oxide–semiconductor technology. This circuit is based on the recombination of two differential paths in quadrature. The proposed vector modulator allows us to generate a phase shift between 0° and 360°. The voltage gain varies between −13 and −9 dB in function of the phase shift generated with a static consumption between 26 and 63 mW depending on its configuration.

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Design of 180°-switched-line phase shifter with constant phase shift using CRLH TL

2014 IEEE Antennas and Propagation Society International Symposium (APSURSI) ◽

10.1109/aps.2014.6904504 ◽

2014 ◽

Cited By ~ 4

Author(s):

Jun Zhang ◽

S.W. Cheung ◽

Qi Zhu

Keyword(s):

Phase Shift ◽

Phase Shifter

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SIMULATION OF CO-PLANAR WAVEGUIDE LIQUID CRYSTAL BASED PHASE SHIFTER

Jurnal Teknologi ◽

10.11113/jt.v77.6294 ◽

2015 ◽

Vol 77 (10) ◽

Author(s):

Nasser A ALQuaiti ◽

Noor Asniza Murad

Keyword(s):

Liquid Crystal ◽

Phase Shift ◽

Phase Shifter ◽

Low Cost ◽

Continuous Phase ◽

Phase Shifting ◽

Telecommunication System ◽

Liquid Crystal Material ◽

Compact Size ◽

5Cb Liquid Crystal

This paper discussed the design and performances of a liquid crystal phase shifter that can be used in tuning devices. Tuning devices growth with the demand in the emerging in telecommunication system. Tuning devices with smooth continuous phase shifting at low cost and compact size would be an advantage. This paper proposed a phase shifter using 5CB liquid crystal material. The advantages of using the material is the smoothness and continuity of the transitions in the phase shift. It is done by having a structure with cavity filled with the liquid crystal and applied with certain voltage that can be changed. The changes in voltage would change the applied electric field, and thus would change the permittivity of the material. The changes would affect the wave propagation and thus contribute to the phase shifting. The performance of the phase shifter was tested by means of simulation using CST Suite 2014 software. The results show that the higher the frequency, the higher the phase shift would occur. The highest FoM achieved is 68 (deg/dB) at 8 GHz. A phase shifter with smooth and continuous phase shift can be used as the feeding network in an array scanning antennas systems.

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Four-Port Dual-Mode Diplexer with High Signal Isolation

Active and Passive Electronic Components ◽

10.1155/2020/4032673 ◽

2020 ◽

Vol 2020 ◽

pp. 1-5

Author(s):

Jessada Konpang ◽

Natchayathorn Wattikornsirikul

Keyword(s):

Phase Shift ◽

Transmission Line ◽

Phase Shifter ◽

High Signal ◽

Dual Mode ◽

High Isolation ◽

Centre Frequency ◽

Phase Cancellation ◽

Signal Isolation

An ease of four-port dual-mode diplexer with high signal isolation is presented. A compact dual-mode diplexer with high signal isolation between the Rx and Tx modules is achievable by only using one resonator filter topology. Two back-to-back dual-mode diplexers have a 180° phase shift in one branch. The high isolation can be achieved by amplitude and phase cancellation technique. The delayed transmission line can be easily achieved by the phase shifter. The simulated and measured four-port dual-mode diplexers are designed at the centre frequency of Rx/Tx at 1.95 GHz and 2.14 GHz, respectively. The measured results of Rx/Tx dual-mode diplexer devices are presented with 47.1 dB Rx/Tx isolation. This four-port dual-mode diplexer achieves the isolation (S32) of more than 24.1 dB when compared with the conventional three-port dual-mode diplexer structure.

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Specific features of penetration and trapping of a magnetic flux in film and bulk YBCO high-temperature superconductors

International Journal of Modern Physics B ◽

10.1142/s0217979218503460 ◽

2018 ◽

Vol 32 (31) ◽

pp. 1850346

Author(s):

Kh. R. Rostami

Keyword(s):

Magnetic Field ◽

High Temperature ◽

Magnetic Flux ◽

External Field ◽

High Temperature Superconductors ◽

Interaction Mechanism ◽

Differential Method ◽

Bulk Ybco ◽

The Magnetic Field ◽

Insight Into

An oscillatory differential method of local diagnostics of superconductors is applied to the analysis of the trapped magnetic flux and the effective demagnetization factor in YBCO samples. Regular steps over certain intervals of the external field are observed on the magnetic-field dependence of these parameters. It is demonstrated that, as the external field increases, crystallites in a sample are decomposed into sub- and nanocrystallites with a size much less than the penetration depth [Formula: see text] of the magnetic field. The first critical thermodynamic magnetic fields of sub- and nanocrystallites are determined. These results allow one to reveal the interaction mechanism between magnetic and crystalline microstructures of superconductors and provide a deeper insight into the physical processes that occur in high-temperature superconductors (HTSCs) in a magnetic field.

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Picosecond Studies of Nonequilibrium Flux Dynamics in Superconductors

MRS Proceedings ◽

10.1557/proc-290-323 ◽

1992 ◽

Vol 290 ◽

Author(s):

M. R. Freeman

Keyword(s):

Magnetic Field ◽

Magnetic Flux ◽

Intermediate State ◽

Nonequilibrium State ◽

Normal Metal ◽

Fast Time ◽

Type I ◽

Superconducting Transition ◽

Local Motion ◽

Flux Dynamics

AbstractA fast time-domain magneto-optical technique is used to explore magnetic flux dynamics in the optically driven nonequilibrium state of Type I superconducting Pb films. It is found that the effective penetration of flux through the nonequilibrium intermediate state can be dramatically faster than through the normal metal. The system is probed through the application of rapid transient magnetic field pulses. Above the superconducting transition temperature, a direct measure of the diffusion coefficient of the magnetic field in the normal metal is obtained, on a time scale where the inhomogeneous spatial distribution of scattering sites is relevant. In the nonequilibrium superconductor the observations are dominated by coupling of the field transients to local motion of magnetic flux threading the normal domains. Studies as a function of how far the system is driven from equilibrium, and of the effect of a static applied magnetic field, indicate that the observations reflect the dynamics of normal/superconducting interfaces, and are strongly dependent on the microscopic arrangement of the intermediate state. By contrasting the response of pure Pb films to that of Pb1−xInx alloys, a comparison to Type II superconductivity is made.

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First Demonstration of a Periodically Loaded Line Phase Shifter Using BST Capacitors

MRS Proceedings ◽

10.1557/proc-603-37 ◽

1999 ◽

Vol 603 ◽

Cited By ~ 3

Author(s):

Amit S. Nagra ◽

Troy R. Taylor ◽

Padmini Periaswamy ◽

James Speck ◽

Robert A. York

Keyword(s):

Phase Shift ◽

Insertion Loss ◽

Parallel Plate ◽

Room Temperature ◽

Phase Shifter ◽

X Band ◽

Fabrication Procedure ◽

Room Temperature Operation

AbstractPeriodically loaded line phase shifter circuits using voltage tunable BaSrTiO3 (BST) parallel plate capacitors have been demonstrated at X-band. The first such phase shifter circuit was capable of 100° of phase shift with an insertion loss of 7.6 dB at 10 GHz. Subsequently, the monolithic fabrication procedure was refined resulting in an improved phase shifter circuit with 200° of phase shift and an insertion loss of 6.2 dB at 10 GHz. In addition to promising loss performance (32°/dB) at 10 GHz, the circuits reported here have several desirable features such as moderate control voltages (20 V), room temperature operation, and compatibility with monolithic fabrication techniques.

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