Multifunctional Ultrahigh Sensitive Microwave Planar Sensor to Monitor Mechanical Motion: Rotation, Displacement, and Stretch

This paper presents a novel planar multifunctional sensor that is used to monitor physical variations in the environment regarding distance, angle, and stretch. A double split-ring resonator is designed at 5.2 GHz as the core operating sensor. Another identical resonator is placed on top of the first one. The stacked configuration is theoretically analyzed using an electric circuit model with a detailed parameter extraction discussion. This design is first employed as a displacement sensor, and a compelling high sensitivity of 500 MHz/mm is observed for a wide dynamic range of 0-5 mm. Then, in another configuration, the stacked design is used as a rotation sensor that results in a high sensitivity of 4.5 MHz/ ° for the full range of 0-180 ° . In addition, the stacked resonator is utilized as a strain detector, and a 0–30% stretch is emulated with a linear sensitivity of 12 MHz/%. Measurements are well in congruence with simulated results, which proves the accurate functionality of the sensor in tracking mechanical deformations, all in a single compact contraption.

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Slow-Scan CCD Observation of Backscattering Patterns in SEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100131176 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1308-1309

Author(s):

F. Ouyang ◽

D. A. Ray ◽

O. L. Krivanek

Keyword(s):

Electron Beam ◽

Electron Microscope ◽

Scanning Electron Microscope ◽

Dynamic Range ◽

High Sensitivity ◽

Lens System ◽

Wide Dynamic Range ◽

Peltier Cooler ◽

Diffraction Patterns ◽

Scanning Electron

Electron backscattering Kikuchi diffraction patterns (BKDP) reveal useful information about the structure and orientation of crystals under study. With the well focused electron beam in a scanning electron microscope (SEM), one can use BKDP as a microanalysis tool. BKDPs have been recorded in SEMs using a phosphor screen coupled to an intensified TV camera through a lens system, and by photographic negatives. With the development of fiber-optically coupled slow scan CCD (SSC) cameras for electron beam imaging, one can take advantage of their high sensitivity and wide dynamic range for observing BKDP in SEM.We have used the Gatan 690 SSC camera to observe backscattering patterns in a JEOL JSM-840A SEM. The CCD sensor has an active area of 13.25 mm × 8.83 mm and 576 × 384 pixels. The camera head, which consists of a single crystal YAG scintillator fiber optically coupled to the CCD chip, is located inside the SEM specimen chamber. The whole camera head is cooled to about -30°C by a Peltier cooler, which permits long integration times (up to 100 seconds).

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Development of imaging plate for a TEM and its characteristics

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100152471 ◽

1989 ◽

Vol 47 ◽

pp. 100-101

Author(s):

N. Mori ◽

T. Oikawa ◽

Y. Harada ◽

J. Miyahara ◽

T. Matsuo

Keyword(s):

Dynamic Range ◽

Protective Layer ◽

High Sensitivity ◽

Imaging Plate ◽

Phosphor Layer ◽

Imaging Device ◽

X Ray Imaging ◽

New Type ◽

Basic Characteristics ◽

Reading System

The Imaging Plate (IP) is a new type imaging device, which was developed for diagnostic x ray imaging. We have reported that usage of the IP for a TEM has many merits; those are high sensitivity, wide dynamic range, and good linearity. However in the previous report the reading system was prototype drum-type-scanner, and IP was also experimentally made, which phosphor layer was 50μm thick with no protective layer. So special care was needed to handle them, and they were used only to make sure the basic characteristics. In this article we report the result of newly developed reading, printing system and high resolution IP for practical use. We mainly discuss the characteristics of the IP here. (Precise performance concerned with the reader and other system are reported in the other article.)Fig.1 shows the schematic cross section of the IP. The IP consists of three parts; protective layer, phosphor layer and support.

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Superhydrophobic gradient wrinkle strain sensor with ultra-high sensitivity and broad strain range for motion monitoring

Journal of Materials Chemistry A ◽

10.1039/d0ta11959h ◽

2021 ◽

Vol 9 (15) ◽

pp. 9634-9643

Author(s):

Zhenming Chu ◽

Weicheng Jiao ◽

Yifan Huang ◽

Yongting Zheng ◽

Rongguo Wang ◽

...

Keyword(s):

Human Body ◽

Full Range ◽

Strain Sensor ◽

Strain Range ◽

High Sensitivity

A graphene-based gradient wrinkle strain sensor with a broad range and ultra-high sensitivity was fabricated by a simple pre-stretching method. It can be applied to the detection of full-range human body motions.

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Demonstration of a high-sensitivity and wide-dynamic-range terahertz graphene hot-electron bolometer with Johnson noise thermometry

Applied Physics Letters ◽

10.1063/5.0030704 ◽

2021 ◽

Vol 118 (1) ◽

pp. 013104

Author(s):

W. Miao ◽

F. M. Li ◽

Z. Z. He ◽

H. Gao ◽

Z. Wang ◽

...

Keyword(s):

Dynamic Range ◽

High Sensitivity ◽

Hot Electron ◽

Johnson Noise ◽

Wide Dynamic Range ◽

Noise Thermometry ◽

Hot Electron Bolometer ◽

Johnson Noise Thermometry

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High-frequency rectifiers based on type-II Dirac fermions

Nature Communications ◽

10.1038/s41467-021-21906-w ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Libo Zhang ◽

Zhiqingzi Chen ◽

Kaixuan Zhang ◽

Lin Wang ◽

Huang Xu ◽

...

Keyword(s):

High Frequency ◽

Dynamic Range ◽

High Sensitivity ◽

High Dynamic Range ◽

Anisotropy Ratio ◽

Dirac Fermions ◽

Topological States ◽

Topological Semimetals ◽

Polarized Surface ◽

Symmetry Protected

AbstractThe advent of topological semimetals enables the exploitation of symmetry-protected topological phenomena and quantized transport. Here, we present homogeneous rectifiers, converting high-frequency electromagnetic energy into direct current, based on low-energy Dirac fermions of topological semimetal-NiTe2, with state-of-the-art efficiency already in the first implementation. Explicitly, these devices display room-temperature photosensitivity as high as 251 mA W−1 at 0.3 THz in an unbiased mode, with a photocurrent anisotropy ratio of 22, originating from the interplay between the spin-polarized surface and bulk states. Device performances in terms of broadband operation, high dynamic range, as well as their high sensitivity, validate the immense potential and unique advantages associated to the control of nonequilibrium gapless topological states via built-in electric field, electromagnetic polarization and symmetry breaking in topological semimetals. These findings pave the way for the exploitation of topological phase of matter for high-frequency operations in polarization-sensitive sensing, communications and imaging.

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A Full-Range Flexible and Printed Humidity Sensor Based on a Solution-Processed P(VDF-TrFE)/Graphene-Flower Composite

Nanomaterials ◽

10.3390/nano11081915 ◽

2021 ◽

Vol 11 (8) ◽

pp. 1915

Author(s):

Shenawar Ali Khan ◽

Muhammad Saqib ◽

Muhammad Muqeet Rehman ◽

Hafiz Mohammad Mutee Ur Rehman ◽

Sheik Abdur Rahman ◽

...

Keyword(s):

Active Layer ◽

Humidity Sensor ◽

High Reliability ◽

Full Range ◽

High Sensitivity ◽

Fast Response ◽

Considerable Change ◽

Relative Humidity Range ◽

Response And Recovery ◽

Proportional Relationship

A novel composite based on a polymer (P(VDF-TrFE)) and a two-dimensional material (graphene flower) was proposed as the active layer of an interdigitated electrode (IDEs) based humidity sensor. Silver (Ag) IDEs were screen printed on a flexible polyethylene terephthalate (PET) substrate followed by spin coating the active layer of P(VDF-TrFE)/graphene flower on its surface. It was observed that this sensor responds to a wide relative humidity range (RH%) of 8–98% with a fast response and recovery time of 0.8 s and 2.5 s for the capacitance, respectively. The fabricated sensor displayed an inversely proportional response between capacitance and RH%, while a directly proportional relationship was observed between its impedance and RH%. P(VDF-TrFE)/graphene flower-based flexible humidity sensor exhibited high sensitivity with an average change of capacitance as 0.0558 pF/RH%. Stability of obtained results was monitored for two weeks without any considerable change in the original values, signifying its high reliability. Various chemical, morphological, and electrical characterizations were performed to comprehensively study the humidity-sensing behavior of this advanced composite. The fabricated sensor was successfully used for the applications of health monitoring and measuring the water content in the environment.

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Complex Permittivity Characterization of Liquid Samples Based on a Split Ring Resonator (SRR)

Sensors ◽

10.3390/s21103385 ◽

2021 ◽

Vol 21 (10) ◽

pp. 3385

Author(s):

Jialu Ma ◽

Jingchao Tang ◽

Kaicheng Wang ◽

Lianghao Guo ◽

Yubin Gong ◽

...

Keyword(s):

Resonant Frequency ◽

Complex Permittivity ◽

Ring Resonator ◽

High Sensitivity ◽

Split Ring Resonator ◽

Debye Model ◽

Split Ring ◽

Liquid Samples ◽

Microwave Sensor

A complex permittivity characterization method for liquid samples has been proposed. The measurement is carried out based on a self-designed microwave sensor with a split ring resonator (SRR), the unload resonant frequency of which is 5.05 GHz. The liquid samples in capillary are placed in the resonant zone of the fabricated senor for high sensitivity measurement. The frequency shift of 58.7 MHz is achieved when the capillary is filled with ethanol, corresponding a sensitivity of 97.46 MHz/μL. The complex permittivity of methanol, ethanol, isopropanol (IPA) and deionized water at the resonant frequency are measured and calibrated by the first order Debye model. Then, the complex permittivity of different concentrations of aqueous solutions of these materials are measured by using the calibrated sensor system. The results show that the proposed sensor has high sensitivity and accuracy in measuring the complex permittivity of liquid samples with volumes as small as 0.13 μL. It provides a useful reference for the complex permittivity characterization of small amount of liquid chemical samples. In addition, the characterization of an important biological sample (inositol) is carried out by using the proposed sensor.

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