Low-frequency parametric amplifier with a selenium rectifier

AbstractThe Casimir force, a quantum mechanical effect, has been observed in several microelectromechanical system (MEMS) platforms. Due to its extreme sensitivity to the separation of two objects, the Casimir force has been proposed as an excellent avenue for quantum metrology. Practical application, however, is challenging due to attractive forces leading to stiction and device failure, called Casimir pull-in. In this work, we design and simulate a Casimir-driven metrology platform, where a time-delay-based parametric amplification technique is developed to achieve a steady-state and avoid pull-in. We apply the design to the detection of weak, low-frequency, gradient magnetic fields similar to those emanating from ionic currents in the heart and brain. Simulation parameters are selected from recent experimental platforms developed for Casimir metrology and magnetic gradiometry, both on MEMS platforms. While a MEMS offers many advantages to such an application, the detected signal must typically be at the resonant frequency of the device, with diminished sensitivity in the low frequency regime of biomagnetic fields. Using a Casimir-driven parametric amplifier, we report a 10,000-fold improvement in the best-case resolution of MEMS single-point gradiometers, with a maximum sensitivity of 6 Hz/(pT/cm) at 1 Hz. Further development of the proposed design has the potential to revolutionize metrology and may specifically enable the unshielded monitoring of biomagnetic fields in ambient conditions.

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A Parametric Amplifier for Weak, Low-Frequency Forces

Volume 6: 11th International Conference on Multibody Systems, Nonlinear Dynamics, and Control ◽

10.1115/detc2015-46273 ◽

2015 ◽

Cited By ~ 4

Author(s):

Amit Dolev ◽

Izhak Bucher

Keyword(s):

Multiple Scales ◽

Low Frequency ◽

Parametric Amplifier ◽

Noise Levels ◽

Signal To Noise ◽

External Excitation ◽

Practical Applications ◽

Analytic Expressions ◽

Frequency Excitation ◽

Selection Of

The present work introduces a tunable parametric amplifier (PA) with a hardening, Duffing-type nonlinearity. By introducing a multi-frequency parametric excitation, one is able to achieve both: (i) High amplification of the weak, low-frequency external excitation (ii) Projection of the low frequency on any natural frequency of the system, thus transforming the low frequency excitation to a frequency band where signal levels are considerably higher. Having developed multiple-scales based expressions for the response of such systems, it is demonstrated that (a) The analytical analysis agrees well with numerically obtained simulations. (b) Both the phase, magnitude and spatial projection of this force on any system’s eigenvector can be retrieved by appropriate selection of parameters, with superior signal to noise levels. Closed form analytic expressions for the sensitivity and gain are derived and analyzed. Additionally, some practical applications envisaged for the proposed method will be outlined.

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A Study on the Fine Structure of the Lateral Line Organ of the Sea Eel

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100073684 ◽

1973 ◽

Vol 31 ◽

pp. 648-649

Author(s):

K. Hama

Keyword(s):

Fine Structure ◽

Electron Microscope ◽

Lateral Line ◽

Low Frequency ◽

Sensory Cells ◽

Apical Surface ◽

Voltage Electron ◽

Sensory Epithelia ◽

Low Frequency Vibration ◽

Transmission Electron

The lateral line organs of the sea eel consist of canal and pit organs which are different in function. The former is a low frequency vibration detector whereas the latter functions as an ion receptor as well as a mechano receptor.The fine structure of the sensory epithelia of both organs were studied by means of ordinary transmission electron microscope, high voltage electron microscope and of surface scanning electron microscope.The sensory cells of the canal organ are polarized in front-caudal direction and those of the pit organ are polarized in dorso-ventral direction. The sensory epithelia of both organs have thinner surface coats compared to the surrounding ordinary epithelial cells, which have very thick fuzzy coatings on the apical surface.

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Lectin Binding to Human Breast Tumor Cells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100090154 ◽

1976 ◽

Vol 34 ◽

pp. 34-35

Author(s):

Robert E. Nordquist ◽

J. Hill Anglin ◽

Michael P. Lerner

Keyword(s):

Carcinoma Cell ◽

Ricinus Communis ◽

Lectin Binding ◽

Low Frequency ◽

Breast Carcinoma Cell Line ◽

Human Breast ◽

Human Breast Tumor ◽

Duct Carcinoma ◽

Specific Antigens ◽

Ricin Agglutinin

A human breast carcinoma cell line (BOT-2) was derived from an infiltrating duct carcinoma (1). These cells were shown to have antigens that selectively bound antibodies from breast cancer patient sera (2). Furthermore, these tumor specific antigens could be removed from the living cells by low frequency sonication and have been partially characterized (3). These proteins have been shown to be around 100,000 MW and contain approximately 6% hexose and hexosamines. However, only the hexosamines appear to be available for lectin binding. This study was designed to use Concanavalin A (Con A) and Ricinus Communis (Ricin) agglutinin for the topagraphical localization of D-mannopyranosyl or glucopyranosyl and D-galactopyranosyl or DN- acetyl glactopyranosyl configurations on BOT-2 cell surfaces.

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Practical High Resolution Microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100101256 ◽

1968 ◽

Vol 26 ◽

pp. 302-303

Author(s):

P. A. Marsh ◽

T. Mullens ◽

D. Price

Keyword(s):

High Resolution ◽

Magnetic Fields ◽

Low Frequency ◽

Resolving Power ◽

Careful Attention ◽

Electron Microscopes ◽

The Relationship ◽

High Resolution Microscopy ◽

New Facilities

It is possible to exceed the guaranteed resolution on most electron microscopes by careful attention to microscope parameters essential for high resolution work. While our experience is related to a Philips EM-200, we hope that some of these comments will apply to all electron microscopes.The first considerations are vibration and magnetic fields. These are usually measured at the pre-installation survey and must be within specifications. It has been our experience, however, that these factors can be greatly influenced by the new facilities and therefore must be rechecked after the installation is completed. The relationship between the resolving power of an EM-200 and the maximum tolerable low frequency interference fields in milli-Oerstedt is 10 Å - 1.9, 8 Å - 1.4, 6 Å - 0.8.

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Simulations of high-resolution images of amorphous silicon films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010014419x ◽

1986 ◽

Vol 44 ◽

pp. 544-545

Author(s):

G. Y. Fan ◽

J. M. Cowley

Keyword(s):

Electron Microscope ◽

High Frequency ◽

Fourier Transformation ◽

Amorphous Materials ◽

Low Frequency ◽

Chromatic Aberration ◽

Structure Information ◽

Frequency Components ◽

High Resolution Images ◽

Spatial Frequency Spectrum

It is well known that the structure information on the specimen is not always faithfully transferred through the electron microscope. Firstly, the spatial frequency spectrum is modulated by the transfer function (TF) at the focal plane. Secondly, the spectrum suffers high frequency cut-off by the aperture (or effectively damping terms such as chromatic aberration). While these do not have essential effect on imaging crystal periodicity as long as the low order Bragg spots are inside the aperture, although the contrast may be reversed, they may change the appearance of images of amorphous materials completely. Because the spectrum of amorphous materials is continuous, modulation of it emphasizes some components while weakening others. Especially the cut-off of high frequency components, which contribute to amorphous image just as strongly as low frequency components can have a fundamental effect. This can be illustrated through computer simulation. Imaging of a whitenoise object with an electron microscope without TF limitation gives Fig. 1a, which is obtained by Fourier transformation of a constant amplitude combined with random phases generated by computer.

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SEM image sharpness analysis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100163174 ◽

1996 ◽

Vol 54 ◽

pp. 142-143

Author(s):

M. T. Postek ◽

A. E. Vladar

Keyword(s):

High Frequency ◽

Low Frequency ◽

Quantitative Information ◽

Primary Electron ◽

Image Sharpness ◽

Critical Dimensions ◽

Sem Image ◽

Frequency Changes ◽

Electron Microscopes ◽

Scanning Electron

Fully automated or semi-automated scanning electron microscopes (SEM) are now commonly used in semiconductor production and other forms of manufacturing. The industry requires that an automated instrument must be routinely capable of 5 nm resolution (or better) at 1.0 kV accelerating voltage for the measurement of nominal 0.25-0.35 micrometer semiconductor critical dimensions. Testing and proving that the instrument is performing at this level on a day-by-day basis is an industry need and concern which has been the object of a study at NIST and the fundamentals and results are discussed in this paper.In scanning electron microscopy, two of the most important instrument parameters are the size and shape of the primary electron beam and any image taken in a scanning electron microscope is the result of the sample and electron probe interaction. The low frequency changes in the video signal, collected from the sample, contains information about the larger features and the high frequency changes carry information of finer details. The sharper the image, the larger the number of high frequency components making up that image. Fast Fourier Transform (FFT) analysis of an SEM image can be employed to provide qualitiative and ultimately quantitative information regarding the SEM image quality.

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