Showing papers on "Coplanar waveguide published in 2015"
TL;DR: In this paper, superconducting microwave-frequency resonators based on NbTiN nanowires were proposed for circuit QED experiments with small electric dipole moments and requiring a magnetic field, such as electrons in single and double quantum dots.
Abstract: We present superconducting microwave-frequency resonators based on NbTiN nanowires. The small cross section of the nanowires minimizes vortex generation, making the resonators resilient to magnetic fields. Measured intrinsic quality factors exceed $2\times 10^5$ in a $6$ T in-plane magnetic field, and $3\times 10^4$ in a $350$ mT perpendicular magnetic field. Due to their high characteristic impedance, these resonators are expected to develop zero-point voltage fluctuations one order of magnitude larger than in standard coplanar waveguide resonators. These properties make the nanowire resonators well suited for circuit QED experiments needing strong coupling to quantum systems with small electric dipole moments and requiring a magnetic field, such as electrons in single and double quantum dots.
148 citations
TL;DR: In this paper, a dual-split-ring-resonator (SRR)-loaded coplanar waveguide (CPW)-fed ultrawideband circular monopole antenna exhibiting dual frequency notch and wideband notch characteristics is presented.
Abstract: This letter presents the design of a compact dual-split-ring-resonator (SRR)-loaded coplanar waveguide (CPW)- fed ultrawideband circular monopole antenna exhibiting dual frequency notch and wideband notch characteristics. The SRR pairs are inductively coupled to the radiator and loaded on the back side of the CPW line. Fabricated prototypes were measured and compared to simulations, and good agreement was obtained.
124 citations
TL;DR: In this paper, a 2.45 GHz broadband rectenna using the grounded coplanar waveguide (GCPW) is proposed, which has good performances of broadband, high mw-dc efficiency and compact structure.
Abstract: This letter presents a compact 2.45 GHz broadband rectenna using the grounded coplanar waveguide (GCPW). A new broadband slot antenna fed by GCPW with a high gain of 10 dBi and a wide half-power beamwidth of 60 $^{\circ}$ is designed as the receiving antenna. By designing an input and an output impedance match network, a compact GCPW rectifying circuit based on the voltage doubler principle is proposed, which has broadband performance and is easy to be integrated with the novel GCPW antenna. The receiving antenna and the rectifying circuit are simulated and measured. The measured results of the rectenna agree well with those of the rectifying circuit, which validate the effectiveness of the design. The microwave-direct current (mw-dc) conversion efficiencies of the rectenna keep higher than 50% within the band from 2.2 to 2.6 GHz at 13 dBm received power on a $900\Omega $ load, and the highest efficiency is 72.5%. This rectenna has good performances of broadband, high mw-dc efficiency and compact structure.
123 citations
TL;DR: The proposed angular displacement and angular velocity sensors based on coplanar waveguide transmission lines and S-shaped split ring resonators are presented and it is shown that the angular velocity can be accurately determined from the time-domain response of a carrier time-harmonic signal tuned at the S-SRR resonance frequency.
Abstract: In this paper, angular displacement and angular velocity sensors based on coplanar waveguide (CPW) transmission lines and S-shaped split ring resonators (S-SRRs) are presented. The sensor consists of two parts, namely a CPW and an S-SRR, both lying on parallel planes. By this means, line-to-resonator magnetic coupling arises, the coupling level being dependent on the line-to-resonator relative angular orientation. The line-to-resonator coupling level is the key parameter responsible for modulating the amplitude of the frequency response seen between the CPW ports in the vicinity of the S-SRR fundamental resonance frequency. Specifically, an amplitude notch that can be visualized in the transmission coefficient is changed by the coupling strength, and it is characterized as the sensing variable. Thus, the relative angular orientation between the two parts is measured, when the S-SRR is attached to a rotating object. It follows that the rotation angle and speed can be inferred either by measuring the frequency response of the S-SRR-loaded line, or the response amplitude at a fixed frequency in the vicinity of resonance. It is in addition shown that the angular velocity can be accurately determined from the time-domain response of a carrier time-harmonic signal tuned at the S-SRR resonance frequency. The main advantage of the proposed device is its small size directly related to the small electrical size of the S-SRR, which allows for the design of compact angular displacement and velocity sensors at low frequencies. Despite the small size of the fabricated proof-of-concept prototype (electrically small structures do not usually reject signals efficiently), it exhibits good linearity (on a logarithmic scale), sensitivity and dynamic range.
122 citations
TL;DR: In this article, a broadband frequency tunable and polarization reconfigurable circularly polarized (CP) antenna is presented, using a novel active electromagnetic band gap (EBG) structure.
Abstract: This paper presents a broadband frequency tunable and polarization reconfigurable circularly polarized (CP) antenna, using a novel active electromagnetic band gap (EBG) structure. The EBG surface employs identical metallic rectangular patch arrays on both sides of a thin substrate, but rotated by 90 $^{\circ}$ from each other. The active bias circuits are also orthogonal for each surface, enabling the reflection phases for orthogonal incident waves to be tuned independently in a wide frequency range. By placing a wideband coplanar waveguide (CPW) fed monopole antenna above the EBG surface, and properly tuning the bias voltages across the varactors in each direction, CP waves can be generated at any desired frequency over a broad band. In accordance with simulations, the measured 3 dB axial ratio (AR) bandwidth reaches 40% (1.03–1.54 GHz), with good input matching $(S_{11})$ and radiation patterns at six presented sampling frequencies. The polarization reconfigurability is verified by simulations and measurements, and shown to be capable of switching between left hand circular polarization (LHCP) and right hand circular polarization (RHCP).
104 citations
19 Jul 2015
TL;DR: In this paper, a bowtie antenna with coplanar waveguide (CPW) feed structure has been designed and measured, and a prototype of the antenna has been fabricated using Makerbot® dual 3D printer and flexible polylactic acid (PLA) and ABS filaments for dielectric and conductive parts of antenna, respectively.
Abstract: This paper presents the feasibility of conductive acrylonitrile butadiene styrene (ABS) materials in the fabrication of flexible three-dimensional (3D) antennas using additive manufacturing method. To demonstrate this application a bowtie antenna with coplanar waveguide (CPW) feed structure has been designed and measured. The prototype of the antenna has been fabricated using Makerbot® dual 3D printer and flexible polylactic acid (PLA) and ABS filaments for dielectric and conductive parts of the antenna, respectively. To our knowledge, this is the first reported antenna fabricated with conductive ABS material. The dielectric properties of the PLA and ABS filaments have been measured using Agilent performance probe. The fabricated antenna possesses compact size, light-weight and mechanically flexible structure. In addition it achieves wide bandwidth of 24.18 % at the center frequency of 7.81 GHz.
90 citations
TL;DR: In this paper, a very small coplanar waveguide (CPW)-fed rectangular slot antenna with dual band-notched characteristics for super ultrawideband (UWB) applications is proposed.
Abstract: A very small coplanar waveguide (CPW)-fed rectangular slot antenna with dual band-notched characteristics for super ultrawideband (UWB) applications is proposed. This antenna consists of a rectangular slot, a beveled rectangular patch, two S-shaped slits cut in the ground plane and an elliptical ring slot (ERS) etched in the patch. The corners of a simple rectangular patch are beveled to improve the impedance bandwidth, especially at the middle frequencies of the band. In addition, a pair of semicircle slots is etched in the ground plane to enhance the bandwidth to more than 23 GHz. A pair of S-shaped slits connected to the rectangular slot, and an ERS cut in the beveled rectangular patch, is employed to create band-notched performances in WiMAX and WLAN spectrum, respectively. The proposed antenna has a very small size of $15 \times 15 \text{mm}^{2}$ , and therefore, it is one of the smallest UWB slot antennas that have been reported until now, and provide a very wide impedance bandwidth from 2.6 to more than 23 GHz for $\text{VSWR} with dual band-notched properties.
76 citations
TL;DR: This work develops MW resonators with optical single spin access and demonstrates coherent control of single nuclear spins under these conditions, and extends the applicable magnetic field range of a single spin magnetic field sensor.
Abstract: Magnetic resonance with ensembles of electron spins is commonly performed around 10 GHz, but also at frequencies above 240 GHz and in corresponding magnetic fields of over 9 T. However, experiments with single electron and nuclear spins so far only reach into frequency ranges of several 10 GHz, where existing coplanar waveguide structures for microwave (MW) delivery are compatible with single spin readout techniques (e.g., electrical or optical readout). Here, we explore the frequency range up to 90 GHz, with magnetic fields of up to ≈3 T for single spin magnetic resonance in conjunction with optical spin readout. To this end, we develop MW resonators with optical single spin access. In our case, rectangular 60-90 GHz (E-band) waveguides guarantee low-loss supply of microwaves to the resonators. Three dimensional cavities, as well as coplanar waveguide resonators, enhance MW fields by spatial and spectral confinement with a MW efficiency of 1.36 mT/√W. We utilize single nitrogen vacancy (NV) centers as hosts for optically accessible spins and show that their properties regarding optical spin readout known from smaller fields (<0.65 T) are retained up to fields of 3 T. In addition, we demonstrate coherent control of single nuclear spins under these conditions. Furthermore, our results extend the applicable magnetic field range of a single spin magnetic field sensor. Regarding spin based quantum registers, high fields lead to a purer product basis of electron and nuclear spins, which promises improved spin lifetimes. For example, during continuous single-shot readout, the (14)N nuclear spin shows second-long longitudinal relaxation times.
74 citations
TL;DR: In this paper, an X-band coplanar waveguide leaky-wave antenna (CPW-LWA) and a Huygens metasurface are fabricated and experimental results verify that the proposed concept can reduce the beam squinting of the LWA by 50% over a 10% bandwidth at angles around broadside.
Abstract: A novel approach is presented to reduce the beam squinting of radiating structures with emphasis on leaky-wave antennas (LWAs). This is achieved by taking advantage of the interesting frequency-dependent variation of the generalized law of refraction in metasurfaces, in combination with the beam-squinting characteristics of LWAs dictated by their dispersion diagram. An X-band coplanar waveguide leaky-wave antenna (CPW-LWA) and a Huygens metasurface are fabricated and experimental results verify that the proposed concept can reduce the beam squinting of the LWA by 50% over a 10% bandwidth at angles around broadside. The proposed method is shown to be an excellent approach to build simple, low-profile, and lowcost communication systems composed of LWAs with low beam-squinting characteristics over a reasonably wide frequency range.
73 citations
TL;DR: This work proposes a high-efficiency transducer using asymmetric coplanar waveguide and slot line to excite the odd-mode SPPs and shows that the fundamental SPP mode on such a plasmonic metamaterial is a tightly confined odd mode, whose dispersion curve can be tuned by the shape of groove.
Abstract: Surface plasmon polaritons (SPPs), either on metal-dielectric interfaces in optical frequencies or on structured metal surfaces in the lower frequencies, are dominantly even modes. Here we discover dominant odd-mode SPPs on a complementary plasmonic metamaterial, which is constructed by complementary symmetric grooves. We show that the fundamental SPP mode on such a plasmonic metamaterial is a tightly confined odd mode, whose dispersion curve can be tuned by the shape of groove. According to the electric field distributions of odd-mode SPPs, we propose a high-efficiency transducer using asymmetric coplanar waveguide and slot line to excite the odd-mode SPPs. Numerical simulations and experimental results validate the high-efficiency excitation and excellent propagation performance of odd-mode SPPs on the complementary plasmonic waveguides in the microwave frequencies.
72 citations
TL;DR: In this paper, a hybrid spin-electromechanical de-vice with tunable couplings by external fields was proposed for implementing quantum information with single NV spins, diamond mechanical resonators, and single microwave photons.
Abstract: We propose and analyze a hybrid device by integrating a microscale diamond beam with a single built-in nitrogen-vacancy (NV) center spin to a superconducting coplanar waveguide (CPW) cavity. We find that under an ac electric field the quantized motion of the diamond beam can strongly couple to the single cavity photons via dielectric interaction. Together with the strong spin-motion interaction via a large magnetic field gradient, it provides a hybrid quantum device where the dia- mond resonator can strongly couple both to the single microwave cavity photons and to the single NV center spin. This enables coherent information transfer and effective coupling between the NV spin and the CPW cavity via mechanically dark polaritons. This hybrid spin-electromechanical de- vice, with tunable couplings by external fields, offers a realistic platform for implementing quantum information with single NV spins, diamond mechanical resonators, and single microwave photons.
TL;DR: In this article, a low-loss sub-millimeter-wave/THz integrated dielectric waveguide is presented, which consists of a highly resistive Silicon (Si) guiding channel bonded to a glass substrate.
Abstract: A low-loss sub-millimeter-wave/THz integrated dielectric waveguide is presented. The proposed waveguide consists of a highly resistive Silicon (Si) guiding channel bonded to a glass substrate. To reduce the waveguide insertion loss due to the glass substrate, part of the substrate below the Si guiding channel is etched. A periodic configuration of supporting beams is used to hold the Si guiding channel over the glass substrate. A low-cost and high-precision fabrication process, which is fully compatible with current Si-based fabrication technologies, is developed for the proposed waveguide. Numerical simulations and experiments are conducted to investigate the performance of the proposed waveguide. Measured attenuation constant of the proposed waveguide is 0.0346 dB/ $\lambda_{0}$ (average value) over the 440–500 GHz band.
TL;DR: In this article, the InP HEMT amplifier achieves a noise figure as low as 11.1 dB with an associated gain of 13.6 dB at 0.85 THz.
Abstract: In this letter, the first packaged THz solid-state amplifier operating at 0.85 THz is reported. The InP HEMT amplifier achieves a noise figure as low as 11.1 dB with an associated gain of 13.6 dB at 0.85 THz using high ${\bf f}_{\bf MAX}$ InP HEMT transistors in a 10-stage coplanar waveguide integrated circuit. Output power up to 0.93 mW is measured.
TL;DR: In this paper, a predictive electrical model of the slow-wave coplanar waveguide structure (S-CPW) is presented under the assumption of Quasi-TEM propagation mode.
Abstract: In this paper, a predictive electrical model of the slow-wave coplanar waveguide structure (S-CPW) is presented. The model was developed under the assumption of Quasi-TEM propagation mode. This assumption allows treating separately the electric field from the magnetic field. Therefore, inductive and capacitive effects are processed apart. Within this context, analytical formulas, parameterized by S-CPW geometric dimensions, are given for each electric parameter in the model, including resistances that account for losses. The model was validated with electromagnetic simulations $({\rm HFSS}^{{{{\rm TM}}}})$ and measurement results on several integrated technologies. An excellent agreement was achieved over a wide frequency band from DC up to 110 GHz, with a maximum error of 10%. Consequently, the model provides a fast and powerful tool for designing circuits based on S-CPW. The developed model enables a better insight of how geometries influence the overall S-CPW performance. The model was applied to the design of a quarter-wave length transmission lines and tunable phase shifter. The transmission lines were optimized in terms of performance, minimum length or surface. The tunable phase shifter was designed by embedding varactors in the S-CPW floating shield. These designs highlight the efficiency of the model for complex optimization or complex circuits design, respectively.
TL;DR: In this paper, a planar slot antenna with microstrip-CPW fed is proposed, which consists of a wide rectangular slot and a coplanar waveguide feedline, both etched on the ground plane of a dielectric substrate.
Abstract: A novel broadband circularly polarized planar slot antenna with microstrip-CPW fed is proposed in this paper. It consists of a wide rectangular slot and a coplanar waveguide (CPW) feedline, both etched on the ground plane of a dielectric substrate, as well as a microstrip to CPW transition on the reverse plane of the substrate. The microstrip-CPW feed structure is appropriately designed so that the even and odd modes of the CPW are excited with $90^\circ $ phase difference, and are then fed to the slot antenna to realize wideband circular polarization operation. The mechanism of circular polarization in this design is explained and the detailed parametric study of the antenna is carried out. The measured 3-dB axial-ratio bandwidth is 39.4% (1.98 $\sim$ 2.95 GHz), and $ - $ 10 dB reflection coefficient bandwidth is 57% (1.73 $\sim $ 3.11 GHz).
TL;DR: In this article, a miniaturized transmission-line sensor based on a coplanar waveguide is used to characterize the permittivity of nanoliter volumes of biologically relevant liquids and cell suspensions.
Abstract: The nondestructive characterization of biological liquids and cell suspensions using electromagnetic waves in the microwave frequency range calls for accurate and sensitive measurement devices. Especially when reducing the sample volume, the sensitivity becomes a critical design parameter for broadband sensors. In this paper, a miniaturized transmission-line sensor based on a coplanar waveguide is used to characterize the permittivity of nanoliter volumes of biologically relevant liquids and cell suspensions. The sensor’s sensitivity is increased by means of electrically small discontinuities within the sensing section. The biological samples are guided across the sensor in a microfluidic channel, which is fabricated using microsystems technology. The sensor is used between 850 MHz and 40 GHz to detect the broadband permittivity of liquid samples such as aqueous salt and protein solutions. The experimentally detected contrast between living and dead Chinese hamster ovary cells in suspension is significant despite the small sample volume.
TL;DR: In this article, a coplanar waveguide-fed triple-band monopole antenna with high-band isolation for various wireless applications is presented, which is composed of a CPW-fed structure and a hexagon-shaped patch on which a hexagonal-shaped slot is etched for covering the wireless local area network (WLAN) band (2.4/5.8 GHz), and occupies a very compact size of 26 × 25 mm2.
Abstract: A compact coplanar waveguide (CPW)-fed triple-band monopole antenna with high-band isolation for various wireless applications is presented. The proposed antenna is composed of a CPW-fed structure and a hexagon-shaped patch on which a hexagon-shaped slot is etched for covering the wireless local area network (WLAN) band (2.4/5.2/5.8 GHz), and occupies a very compact size of 26 × 25 mm2. By introducing a half-hexagon-shaped stub, additional bands can be realised covering the worldwide interoperability for microwave access (WIMAX) band (2.5/3.5/5.5 GHz). The proposed antenna has been fabricated and measured; results show a higher isolation between adjacent bands, good radiation pattern characteristics and stable gains in the operating bands. The simple feeding structure, compact size and uniplanar design make it easy to be integrated within portable devices for wireless communication.
TL;DR: In this paper, a high-quality transition from coplanar waveguide to empty coaxial line is proposed, which is suitable to develop completely substrate-integrated components for applications in wideband communication systems that require high quality responses and protection from external interferences.
Abstract: Recently, a new empty coaxial structure, entirely built with printed circuit boards, has been proposed. The resulting coaxial line has low radiation, low losses, high-quality factor, and is nondispersive. Up to now, this coaxial line has not been completely integrated in a planar substrate, since a working transition to a traditional planar line has not been defined yet. Therefore, in this paper, a high-quality transition from coplanar waveguide to this new empty coaxial line is proposed. With this transition, the coaxial line is completely integrated in a planar circuit board, so that it truly becomes an empty substrate-integrated coaxial line. The proposed transition has been fabricated. Both full-wave simulated and measured results show an excellent agreement. Therefore, the proposed transition is suitable to develop completely substrate-integrated components for applications in wideband communication systems that require very high quality responses and protection from external interferences. To show this fact, this new transition has been applied to integrate a high-performance empty coaxial filter in a planar substrate. The measured response of this filter is excellent, and proves the goodness of the proposed transition that has enabled, for the first time, the complete integration of an empty coaxial line in a planar substrate.
TL;DR: In this article, a Josephson parametric amplifier based on a flux-tunable quarter-wavelength resonator is characterized and compared with degenerate and non-degenerate parametric amplification using a pair of modes.
Abstract: We characterize a Josephson parametric amplifier based on a flux-tunable quarter-wavelength resonator. The fundamental resonance frequency is ∼1 GHz, but we use higher modes of the resonator for our measurements. An on-chip tuning line allows for magnetic flux pumping of the amplifier. We investigate and compare degenerate parametric amplification, involving a single mode, and nondegenerate parametric amplification, using a pair of modes. We show that we reach quantum-limited noise performance in both cases.
TL;DR: In this article, a new style of broadband bow-tie slot antenna with an improved gain is presented, which is fed by an asymmetric coplanar waveguide (ACPW) with different slot lengths.
Abstract: In this communication, a new style of broadband bow-tie slot antenna with an improved gain is presented. It is fed by an asymmetric coplanar waveguide (ACPW) with different slot lengths. By adjusting the length of one ACPW slot, the impedance characteristic of the antenna is greatly improved so that the bandwidth is broadened. Meanwhile, to improve the gain at low frequency band, a loop strip is added in the bow-tie slot. The simulated and measured results show that the proposed antenna can operate from 2.76 GHz to 8.1 GHz and the relative bandwidth is 100.4%. Furthermore, the flatter gain within the operating frequency band is obtained and the maximum gain at beam peak reaches 5.53 dBi.
TL;DR: In this framework, a variety of band-notched devices and antennas in the microwave and terahertz frequencies can be easily designed without additional band-stop filters.
Abstract: This Letter proposes a simple band-notched coplanar waveguide (BNCPW), which consists of a coplanar waveguide (CPW) and an ultra-thin periodic corrugated metallic strip that supports spoof surface plasmon polaritons (SSPPs) with defect units on the back of the substrate. By introducing a defect unit or multiple defect units into the strip, a narrow stopband or multiple narrow stopbands would be generated flexibly and conveniently. The band-notch function is based on the idea that a defect mode, which exists in the bandgap between the fundamental and the first higher mode of the SSPPs, can be introduced to form a stopband. Thus, the SSPPs field is localized around the defect units, which is another form of localized spoof surface plasmons (LSSPs). By properly tuning the dimensions of each defect unit, the absorption level and center frequency of the stopband could be adjusted independently. We offer theoretical analysis and experimental results to validate our idea and design. In this framework, a variety of band-notched devices and antennas in the microwave and terahertz (THz) frequencies can be easily designed without additional band-stop filters.
TL;DR: In this paper, a two-step transition between a CMOS chip and a WR-10 waveguide is investigated and measured results show a bandwidth of 49% (67-110 GHz), an average insertion loss of 0.35 dB, and return loss below 1 dB throughout the entire band.
Abstract: In this paper a two-step transition between a CMOS chip and a WR-10 waveguide is investigated. The transition between a coplanar waveguide (CPW) on Duroid to W-band aluminum waveguide is studied and measured results show a bandwidth of 49% (67–110 GHz), an average insertion loss of 0.35 dB, and return loss below ${-}{\hbox{10}}$ dB throughout the entire band. Wire-bonding is then investigated as a connection between on-chip CMOS ground–signal–ground (GSG) pads to the Duroid CPW where the CMOS to printed circuit board transition measured results show an average 1-dB loss (including the CMOS GSG launcher) in the W-band. The full transition is also used to demonstrate packaging of a 100-GHz voltage-controlled oscillator in 90-nm CMOS where the RF signal was transmitted successfully with an average 2.5-dB loss (which includes a 2-cm Duroid CPW line) compared to on-chip probing measurement results.
TL;DR: In this article, a 1.57 GHz microstrip patch antenna based on simple inkjet printer with improved performance using silver nanoparticles ink is developed, which is printed on a kind of flexible substrate "glossy paper" to offer the advantage of light and flexibility for different applications.
Abstract: A new, efficient, flexible, and cheap antenna designed at 1.57 GHz microstrip patch antenna based on simple inkjet printer with improved performance using silver nanoparticles ink is developed. The antenna is printed on a kind of flexible substrate “glossy paper,” to offer the advantage of light and flexibility for different applications. The performance of silver nanoparticles ink has been studied through inkjet printing versus postsynthesis annealing and multilayer printing. The conductivity has been improved to have promising values up to 2 Ω/cm at temperatures up to 180°C. The surface morphology of the circuits has been analyzed using SEM with mean diameter of the nanoparticles around 100 nm, uniform surface distribution, and mean thickness of the printed layer around 230 microns. Also, a simple design of a coplanar waveguide (CPW) monopole Z-shaped antenna has been considered as an application of fabricated printed antenna using the studied silver nanoparticles ink through a cheap printer.
TL;DR: In this article, a printed multiband coplanar waveguide (CPW)-fed inverted-F antenna (IFA) is presented for universal serial bus (USB) applications, which is designed to operate at GSM 1.8 GHz, Bluetooth 2.4 GHz, WiMAX 3.5 GHz, and WLAN 5.2 GHz.
Abstract: A printed multiband coplanar waveguide (CPW)-fed inverted-F antenna (IFA) is presented in this letter. The concept of loading a printed-IFA with composite right/left-handed (CRLH) unit cells is theoretically and experimentally investigated by using electromagnetic simulators, Advanced Design System (ADS) and High Frequency Structure Simulator (HFSS), for universal serial bus (USB) applications. The proposed USB antenna structure consists of a CPW printed-IFA with two arms loaded by two CRLH unit cells to achieve two extra operating bands in addition to the two fundamental resonant frequencies of two IFA arms. The structure is designed to operate at GSM 1.8 GHz, Bluetooth 2.4 GHz, WiMAX 3.5 GHz, and WLAN 5.2 GHz. Measured and simulated results are in good agreement with the theoretical predictions.
TL;DR: In this paper, the frequency range up to 90 GHz was explored for single spin magnetic resonance in conjunction with optical spin readout, where rectangular E-band waveguides guarantee low-loss supply of microwaves to the resonators, and three dimensional cavities, as well as coplanar waveguide resonators enhanced MW fields by spatial and spectral confinement.
Abstract: Magnetic resonance with ensembles of electron spins is nowadays performed in frequency ranges up to 240 GHz and in corresponding magnetic fields of up to 10 T. However, experiments with single electron and nuclear spins so far only reach into frequency ranges of several 10 GHz, where existing coplanar waveguide structures for microwave (MW) delivery are compatible with single spin readout techniques (e.g. electrical or optical readout). Here, we explore the frequency range up to 90 GHz, respectively magnetic fields of up to $\approx 3\,$T for single spin magnetic resonance in conjunction with optical spin readout. To this end, we develop MW resonators with optical single spin access. In our case, rectangular E-band waveguides guarantee low-loss supply of microwaves to the resonators. Three dimensional cavities, as well as coplanar waveguide resonators enhance MW fields by spatial and spectral confinement with a MW efficiency of $1.36\,\mathrm{mT/\sqrt{W}}$. We utilize single NV centers as hosts for optically accessible spins, and show, that their properties regarding optical spin readout known from smaller fields (<0.65 T) are retained up to fields of 3 T. In addition, we demonstrate coherent control of single nuclear spins under these conditions. Furthermore, our results extend the applicable magnetic field range of a single spin magnetic field sensor. Regarding spin based quantum registers, high fields lead to a purer product basis of electron and nuclear spins, which promises improved spin lifetimes. For example, during continuous single-shot readout the $^{14}$N nuclear spin shows second-long longitudinal relaxation times.
TL;DR: In this article, the authors proposed an effective way to build efficient miniature C-band filters using high-permittivity ceramics, which allowed them to work with shorter wavelengths.
Abstract: This paper introduces an effective way to build efficient miniature C-band filters using high-permittivity ceramics. The objective was to evaluate the feasibility of such filters using commercial electromagnetic simulators and a conventional fabrication process. For the demonstration, the substrate integrated waveguide (SIW) technology was chosen. Compared with planar solutions, this configuration offers good quality factors and good electrical performances as a consequence. However, its dimensions are large, leading to unacceptably large footprints for many applications. The solution proposed in this paper is based on a ceramic substrate with a permittivity of 90, which allowed us to work with shorter wavelengths. In comparison with a standard alumina substrate (permittivity $\varepsilon _{r}= 9.9$ ), this approach makes it possible to reduce the footprint up to nine times. Two prototypes were realized on a Trans-Tech ceramic substrate ( ${\rm thickness}=635~\mu \text{m}$ , $\varepsilon _{r} = 90$ , and tan $\delta = 9\cdot 10^{-4})$ . The first prototype is a folded sixth-order SIW filter including a cross coupling combining coplanar waveguide probes and a thin microstrip line on an InterVia substrate. The second one is a folded eighth-order SIW filter without cross couplings. Here, we compare the sixth-order prototype with an identical one built on alumina. The eighth-order filter, which had no alumina counterpart, is a potentially useful alternative for situations where complex technological steps must be avoided.
TL;DR: In this paper, a coplanar waveguide transducer is used to generate two-dimensional spin wave beams in thin homogeneous ferromagnetic films, which can then be used to accelerate the beam over distances of several micrometers.
Abstract: We present an approach enabling generation of narrow spin wave beams in thin homogeneous ferromagnetic films. The main idea is to match the wave vector of the spin wave with that corresponding to the spectral maximum of the exciting microwave magnetic field only locally, in the region of space from which the beam should be launched. We show that this can be achieved with the aid of a properly designed coplanar waveguide transducer generating a nonuniform microwave magnetic field. The resulting two-dimensional spin wave beams obtained in micromagnetic simulations propagate over distances of several micrometers. The proposed approach requires neither inhomogeneity of the ferromagnetic film nor nonuniformity of the biasing magnetic field, and it can be generalized to yield multiple spin wave beams of different width at the same frequency. Other possible excitation scenarios and applications of spin wave beam magnonics are also discussed.
TL;DR: In this article, a high dynamic range microwave power sensor compatible with the gallium arsenide monolithic microwave integrated circuit process is presented, which consists of a thermoelectric power sensor and a capacitive power sensor for low and high power detection.
Abstract: A high dynamic range microwave power sensor compatible with the gallium arsenide monolithic microwave integrated circuit process is presented. The power sensor consists of a thermoelectric power sensor and a capacitive power sensor for low and high power detection, respectively. To improve the dynamic range and optimise the impedance matching characteristic, the curled cantilever beam is utilised and the slot width of the coplanar waveguide transmission line is modified. The measured return loss is lower than –25.5 dB at 8–12 GHz. The output of the power sensor shows good linearity with the incident radio frequency power. For the incident power from 0.1 to 100 mW, the obtained sensitivities by a thermoelectric power sensor are about 0.0842, 0.0752 and 0.0701 mV/mW at 8, 10 and 12 GHz, respectively. For the incident power from 100 to 400 mW, the measured sensitivities by the capacitive power senor are about 0.0400, 0.0301 and 0.199 fF/mW at 8, 10 and 12 GHz, respectively.
TL;DR: In this article, a triple band notched coplanar waveguide fed planar monopole antenna is presented for ultrawideband applications, which is achieved using a novel mushroom type electromagnetic band gap structure like resonator and a split ring slot.
Abstract: To mitigate the interference with coexisting wireless systems operating over 3.3-3.6 GHz, 5.15-5.825 GHz, and 7.725-8.5 GHz bands, a novel triple band notched coplanar waveguide fed pitcher-shaped planar monopole antenna is presented for ultrawideband applications. Bands notched characteristics are achieved using a novel mushroom type electromagnetic band gap structure like resonator and a split ring slot. A conceptual equivalent RLC Resistor-Inductor-Capacitor-resonant circuit is presented for the band notched characteristics. Furthermore, the input impedance and VSWR voltage standing wave ratio obtained from the equivalent circuit are validated with simulated and measured results. Performances of the antennas in both, the frequency domain and the time domain are investigated. The simulated and measured results demonstrate that the proposed antennas have wide impedance bandwidth, nearly stable radiation patterns, and suppression of gain and total radiation efficiency at notched bands. © 2015 Wiley Periodicals, Inc. Int J RF and Microwave CAE 25:795-806, 2015.
TL;DR: In this paper, an implantable coplanar waveguide (CPW) fed monopole U Slot antenna at industrial scientific and medical (ISM) band for biomedical applications is proposed.
Abstract: In this chapter, an implantable coplanar waveguide (CPW) fed monopole U Slot antenna at industrial scientific and medical (ISM) band for biomedical applications is proposed. The proposed antenna has a overall dimensions of 29 mm × 29 mm × 0.5 mm at the ISM band (2.4–2.48 GHz). The proposed antenna placed on human tissues like skin, fat, and muscle. The designed antenna is made compatible for implantation by embedding it on RT Duroid substrate and the 10 dB return loss bandwidth is 5.24% ranging from 2.35 to 2.5 GHz. Implantable CPW fed monopole slot antennas are being significantly used into implantable medical devices and RF, because of its merits like conformability, flexibility in design and shape and also it has biocompatibility, patient safety, miniaturization, power consumption etc. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:1604–1608, 2015