scholarly journals PRECISION MEASUREMENT OF THE CASIMIR FORCE FOR Au USING A DYNAMIC AFM

2012 ◽  
Vol 14 ◽  
pp. 270-280 ◽  
Author(s):  
C.-C. CHANG ◽  
A. A. BANISHEV ◽  
R. CASTILLO-GARZA ◽  
G. L. KLIMCHITSKAYA ◽  
V. M. MOSTEPANENKO ◽  
...  
Keyword(s):  
Experimental Data ◽  
Precision Measurement ◽  
Casimir Force ◽  
High Vacuum ◽  
Measurement Range ◽  
Plasma Model ◽  
Atomic Force ◽  
Surface Contaminants ◽  
Modulation Regime ◽  
Model Approach

The gradient of the Casimir force between carefully cleaned Au surfaces of a sphere and a plate is measured using a dynamic atomic force microscope in the frequency modulation regime in high vacuum. The electrostatic calibration of the setup did not reveal any effect of patches or surface contaminants. The experimental data for the force gradient are found to be consistent with theory using the plasma model approach over the entire measurement range. The Drude model approach is excluded by the data at separations from 235 to 400 nm at a 67% confidence level.

scholarly journals OBSERVATION OF THE THERMAL CASIMIR FORCE IS OPEN TO QUESTION

2011 ◽  
Vol 03 ◽  
pp. 515-526 ◽  
Author(s):  
G. L. KLIMCHITSKAYA ◽  
M. BORDAG ◽  
E. FISCHBACH ◽  
D. E. KRAUSE ◽  
V. M. MOSTEPANENKO
Keyword(s):  
Experimental Data ◽  
Casimir Force ◽  
Drude Model ◽  
Plasma Model ◽  
Theoretical Predictions ◽  
Proximity Force Approximation ◽  
Experimental Errors ◽  
Recent Claim ◽  
Model Approach

We discuss theoretical predictions for the thermal Casimir force and compare them with available experimental data. Special attention is paid to the recent claim of the observation of that effect, as predicted by the Drude model approach. We show that this claim is in contradiction with a number of experiments reported so far. We suggest that the experimental errors, as reported in support of the observation of the thermal Casimir force, are significantly underestimated. Furthermore, the experimental data at separations above 3 μm are shown to be in agreement not with the Drude model approach, as is claimed, but with the plasma model. The seeming agreement of the data with the Drude model at separations below 3 μm is explained by the use of an inadequate formulation of the proximity force approximation.

scholarly journals OBSERVATION OF THE THERMAL CASIMIR FORCE IS OPEN TO QUESTION

2011 ◽  
Vol 26 (22) ◽  
pp. 3918-3929 ◽  
Author(s):  
G. L. KLIMCHITSKAYA ◽  
M. BORDAG ◽  
E. FISCHBACH ◽  
D. E. KRAUSE ◽  
V. M. MOSTEPANENKO
Keyword(s):  
Experimental Data ◽  
Casimir Force ◽  
Drude Model ◽  
Plasma Model ◽  
Theoretical Predictions ◽  
Proximity Force Approximation ◽  
Experimental Errors ◽  
Recent Claim ◽  
Model Approach

We discuss theoretical predictions for the thermal Casimir force and compare them with available experimental data. Special attention is paid to the recent claim of the observation of that effect, as predicted by the Drude model approach. We show that this claim is in contradiction with a number of experiments reported so far. We suggest that the experimental errors, as reported in support of the observation of the thermal Casimir force, are significantly underestimated. Furthermore, the experimental data at separations above 3μm are shown to be in agreement not with the Drude model approach, as is claimed, but with the plasma model. The seeming agreement of the data with the Drude model at separations below 3 μm is explained by the use of an inadequate formulation of the proximity force approximation.

CRITICAL STEPS IN DATA ANALYSIS FOR PRECISION CASIMIR FORCE MEASUREMENTS WITH SEMICONDUCTING FILMS

2011 ◽  
Vol 26 (22) ◽  
pp. 3900-3909 ◽  
Author(s):  
A. A. BANISHEV ◽  
CHIA-CHENG CHANG ◽  
U. MOHIDEEN
Keyword(s):  
Data Analysis ◽  
Indium Tin Oxide ◽  
Casimir Force ◽  
High Vacuum ◽  
Force Measurements ◽  
Uv Treatment ◽  
Critical Data ◽  
Ito Film ◽  
Atomic Force ◽  
Gold Sphere

Some experimental procedures and corresponding results of the precision measurement of the Casimir force between low doped Indium Tin Oxide ( ITO ) film and gold sphere are described. Measurements were performed using an Atomic Force Microscope in high vacuum. It is shown that the magnitude of the Casimir force decreases after prolonged UV treatment of the ITO film. Some critical data analysis steps such as the correction for the mechanical drift of the sphere-plate system and photodiodes are discussed.

scholarly journals CRITICAL STEPS IN DATA ANALYSIS FOR PRECISION CASIMIR FORCE MEASUREMENTS WITH SEMICONDUCTING FILMS

2011 ◽  
Vol 03 ◽  
pp. 497-506 ◽  
Author(s):  
A. A. BANISHEV ◽  
CHIA-CHENG CHANG ◽  
U. MOHIDEEN
Keyword(s):  
Data Analysis ◽  
Indium Tin Oxide ◽  
Casimir Force ◽  
High Vacuum ◽  
Force Measurements ◽  
Uv Treatment ◽  
Critical Data ◽  
Ito Film ◽  
Atomic Force ◽  
Gold Sphere

Some experimental procedures and corresponding results of the precision measurement of the Casimir force between low doped Indium Tin Oxide (ITO) film and gold sphere are described. Measurements were performed using an Atomic Force Microscope in high vacuum. It is shown that the magnitude of the Casimir force decreases after prolonged UV treatment of the ITO film. Some critical data analysis steps such as the correction for the mechanical drift of the sphere-plate system and photodiodes are discussed.

Prospects for scanned-probe microscopy

1994 ◽  
Vol 52 ◽  
pp. 6-7
Author(s):  
Jean-Paul Revel
Keyword(s):  
High Vacuum ◽  
Physiological Saline ◽  
Scanning Probe ◽  
Aqueous Environment ◽  
Whole Cells ◽  
Material Scientist ◽  
Biological Objects ◽  
Spatially Resolved ◽  
Atomic Force ◽  
Scanned Probe Microscopy

In the last 50+ years the electron microscope and allied instruments have led the way as means to acquire spatially resolved information about very small objects. For the material scientist and the biologist both, imaging using the information derived from the interaction of electrons with the objects of their concern, has had limitations. Material scientists have been handicapped by the fact that their samples are often too thick for penetration without using million volt instruments. Biologists have been handicapped both by the problem of contrast since most biological objects are composed of elements of low Z, and also by the requirement that sample be placed in high vacuum. Cells consist of 90% water, so elaborate precautions have to be taken to remove the water without losing the structure altogether. We are now poised to make another leap forwards because of the development of scanned probe microscopies, particularly the Atomic Force Microscope (AFM). The scanning probe instruments permit resolutions that electron microscopists still work very hard to achieve, if they have reached it yet. Probably the most interesting feature of the AFM technology, for the biologist in any case, is that it has opened the dream of high resolution in an aqueous environment. There are few restrictions on where the instrument can be used. AFMs can be made to work in high vacuum, allowing the material scientist to avoid contamination. The biologist can be made happy as well. The tips used for detection are made of silicon nitride,(Si3N4), and are essentially unaffected by exposure to physiological saline (about which more below). So here is an instrument which can look at living whole cells and at atoms as well.

scholarly journals Influence of the Porosity of Polymer Foams on the Performances of Capacitive Flexible Pressure Sensors

Sensors ◽  
2019 ◽  
Vol 19 (9) ◽  
pp. 1968 ◽  
Author(s):  
Sylvie Bilent ◽  
Thi Hong Nhung Dinh ◽  
Emile Martincic ◽  
Pierre-Yves Joubert
Keyword(s):  
Experimental Data ◽  
Linear Model ◽  
Dielectric Material ◽  
Pressure Sensors ◽  
Volume Ratio ◽  
Measurement Range ◽  
Polymer Foams ◽  
First Order ◽  
Non Linear ◽  
Flexible Pressure Sensors

This paper reports on the study of microporous polydimethylsiloxane (PDMS) foams as a highly deformable dielectric material used in the composition of flexible capacitive pressure sensors dedicated to wearable use. A fabrication process allowing the porosity of the foams to be adjusted was proposed and the fabricated foams were characterized. Then, elementary capacitive pressure sensors (15 × 15 mm2 square shaped electrodes) were elaborated with fabricated foams (5 mm or 10 mm thick) and were electromechanically characterized. Since the sensor responses under load are strongly non-linear, a behavioral non-linear model (first order exponential) was proposed, adjusted to the experimental data, and used to objectively estimate the sensor performances in terms of sensitivity and measurement range. The main conclusions of this study are that the porosity of the PDMS foams can be adjusted through the sugar:PDMS volume ratio and the size of sugar crystals used to fabricate the foams. Additionally, the porosity of the foams significantly modified the sensor performances. Indeed, compared to bulk PDMS sensors of the same size, the sensitivity of porous PDMS sensors could be multiplied by a factor up to 100 (the sensitivity is 0.14 %.kPa−1 for a bulk PDMS sensor and up to 13.7 %.kPa−1 for a porous PDMS sensor of the same dimensions), while the measurement range was reduced from a factor of 2 to 3 (from 594 kPa for a bulk PDMS sensor down to between 255 and 177 kPa for a PDMS foam sensor of the same dimensions, according to the porosity). This study opens the way to the design and fabrication of wearable flexible pressure sensors with adjustable performances through the control of the porosity of the fabricated PDMS foams.

scholarly journals Set-up of a high-resolution 300 mK atomic force microscope in an ultra-high vacuum compatible 3He/10 T cryostat

2016 ◽  
Vol 87 (7) ◽  
pp. 073702 ◽  
Author(s):  
H. von Allwörden ◽  
K. Ruschmeier ◽  
A. Köhler ◽  
T. Eelbo ◽  
A. Schwarz ◽  
...  
Keyword(s):  
High Resolution ◽  
Atomic Force Microscope ◽  
High Vacuum ◽  
Ultra High Vacuum ◽  
Atomic Force ◽  
Set Up

TiO2/SiO2 multilayer as an antireflective and protective coating deposited by microwave assisted magnetron sputtering

2013 ◽  
Vol 21 (2) ◽  
Author(s):  
M. Mazur ◽  
D. Wojcieszak ◽  
J. Domaradzki ◽  
D. Kaczmarek ◽  
S. Song ◽  
...  
Keyword(s):  
Magnetron Sputtering ◽  
High Vacuum ◽  
Visible Spectrum ◽  
Ultra High Vacuum ◽  
Protective Film ◽  
Wetting Properties ◽  
Microwave Assisted ◽  
Atomic Force ◽  
Packed Structure ◽  
Protective Performance

AbstractIn this paper designing, preparation and characterization of multifunctional coatings based on TiO2/SiO2 has been described. TiO2 was used as a high index material, whereas SiO2 was used as a low index material. Multilayers were deposited on microscope slide substrates by microwave assisted reactive magnetron sputtering process. Multilayer design was optimized for residual reflection of about 3% in visible spectrum (450–800 nm). As a top layer, TiO2 with a fixed thickness of 10 nm as a protective film was deposited. Based on transmittance and reflectance spectra, refractive indexes of TiO2 and SiO2 single layers were calculated. Ultra high vacuum atomic force microscope was used to characterize the surface properties of TiO2/SiO2 multilayer. Surface morphology revealed densely packed structure with grains of about 30 nm in size. Prepared samples were also investigated by nanoindentation to evaluate their protective performance against external hazards. Therefore, the hardness of the thin films was measured and it was equal to 9.34 GPa. Additionally, contact angle of prepared coatings has been measured to assess the wetting properties of the multilayer surface.

scholarly journals Direct-write polymer nanolithography in ultra-high vacuum

2012 ◽  
Vol 3 ◽  
pp. 52-56 ◽  
Author(s):  
Woo-Kyung Lee ◽  
Minchul Yang ◽  
Arnaldo R Laracuente ◽  
William P King ◽  
Lloyd J Whitman ◽  
...  
Keyword(s):  
Atomic Force Microscope ◽  
Silicon Oxide ◽  
High Vacuum ◽  
Polymer Chains ◽  
Ultra High Vacuum ◽  
Direct Write ◽  
Polymer Nanostructures ◽  
Atomic Force

Polymer nanostructures were directly written onto substrates in ultra-high vacuum. The polymer ink was coated onto atomic force microscope (AFM) probes that could be heated to control the ink viscosity. Then, the ink-coated probes were placed into an ultra-high vacuum (UHV) AFM and used to write polymer nanostructures on surfaces, including surfaces cleaned in UHV. Controlling the writing speed of the tip enabled the control over the number of monolayers of the polymer ink deposited on the surface from a single to tens of monolayers, with higher writing speeds generating thinner polymer nanostructures. Deposition onto silicon oxide-terminated substrates led to polymer chains standing upright on the surface, whereas deposition onto vacuum reconstructed silicon yielded polymer chains aligned along the surface.

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