Quantum transition and decoherence of levitating polaron on helium film thickness under an electromagnetic field

A theory of the liquid helium film on the general lines of that due to Schiff (1941) is proposed, the attraction between the walls of the container and the helium atoms being balanced against gravity, but the wave-like nature of the helium atoms and their mutual attractions are now considered. The predictions of the variation of film thickness with height agree with experiment in order of magnitude. A start is made on the problem of calculating the variation of film thickness with temperature, and a new interpretation of the rate of transfer of helium by the film is suggested.

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The thickness of the saturated helium film above and below the λ -point

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1957.0080 ◽

1957 ◽

Vol 240 (1221) ◽

pp. 243-264 ◽

Cited By ~ 25

Keyword(s):

Film Thickness ◽

Thin Layer ◽

Metal Surface ◽

Calibration Curve ◽

Extreme Temperature ◽

Bulk Liquid ◽

Refractive Indices ◽

Helium Film ◽

Polished Metal ◽

Λ Point

The properties of the static helium film covering a vertical, polished metal surface, at heights between 0∙4 and 1∙6 cm above bulk liquid and from 1∙2 to 3∙8°K, have been reinvestigated using an improved form of apparatus based on the optical method of Burge & Jackson (1951). The original calibration curve of the instrument was found to be incorrect by about 30%, and an entirely new one has been constructed in which the only assumption is that the refractive indices of film and bulk liquid are the same. At 2∙05°K the film thickness d is given by d = k / H 1/ z , where H is the height above bulk liquid, k = 3∙15 x 10 –6 cm and z = 2∙3. The value of z increases to about 2∙6 as the temperature falls to 1∙32°K , but at temperatures below 2∙05°K it varies slightly with height. The value of k varies little between 1∙2 and 3∙8°K, and it has been shown that the film is essentially the same above and below the λ -point. This confirms the theories of the film which are based primarily on van der Waals’s forces of attraction, and it seems clear that the existence of the film is not connected with the λ -phenomenon. Below the λ -point a thin layer of solid air on the metal surface increases the static film thickness enormously. Above the λ -point this phenomenon does not occur, but extreme temperature homogeneity is necessary in order that the film may form. The differences between these results and those of other investigations of the film are discussed.

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Determination of the vapor film thickness at steady superfluid helium film boiling

Journal of Physics Conference Series ◽

10.1088/1742-6596/1359/1/012050 ◽

2019 ◽

Vol 1359 ◽

pp. 012050

Author(s):

Yu Yu Puzina ◽

A P Kryukov ◽

I A Yachevsky

Keyword(s):

Film Thickness ◽

Superfluid Helium ◽

Film Boiling ◽

Vapor Film ◽

Helium Film

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Surface Films on Zircaloy-2 Samples Cracked in Neutral Aqueous NaCl by Stress Corrosion

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100070679 ◽

1973 ◽

Vol 31 ◽

pp. 46-47

Author(s):

R.A. Ploc

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Film Thickness ◽

Stress Corrosion ◽

Zirconium Dioxide ◽

Surface Film ◽

Surface Films ◽

Continuous Layer ◽

Transmission Electron ◽

Product Film

Samples of low-nickel Zircaloy-2 (material MLI-788-see(1)), when anodically polarized in neutral 5 wt% NaCl solutions, were found to be susceptible to pitting and stress corrosion cracking. The SEM revealed that pitting of stressed samples was occurring below a 2000Å thick surface film which behaved differently from normal zirconium dioxide in that it did not display interference colours. Since the initial film thickness was approximately 65Å, attempts were made to examine the product film by transmission electron microscopy to deduce composition and how the corrosion environment could penetrate the continuous layer.

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(111) Monocrystalline Nickel Films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100095819 ◽

1972 ◽

Vol 30 ◽

pp. 512-513

Author(s):

T.E. Pratt ◽

R.W. Vook

Keyword(s):

Film Thickness ◽

Deposition Rate ◽

Room Temperature ◽

Narrow Range ◽

High Vacuum ◽

Residual Pressure ◽

Temperature Dependent ◽

Deposition Parameters ◽

Transmission Electron ◽

Substrate Temperatures

(111) oriented thin monocrystalline Ni films have been prepared by vacuum evaporation and examined by transmission electron microscopy and electron diffraction. In high vacuum, at room temperature, a layer of NaCl was first evaporated onto a freshly air-cleaved muscovite substrate clamped to a copper block with attached heater and thermocouple. Then, at various substrate temperatures, with other parameters held within a narrow range, Ni was evaporated from a tungsten filament. It had been shown previously that similar procedures would yield monocrystalline films of CU, Ag, and Au.For the films examined with respect to temperature dependent effects, typical deposition parameters were: Ni film thickness, 500-800 A; Ni deposition rate, 10 A/sec.; residual pressure, 10-6 torr; NaCl film thickness, 250 A; and NaCl deposition rate, 10 A/sec. Some additional evaporations involved higher deposition rates and lower film thicknesses.Monocrystalline films were obtained with substrate temperatures above 500° C. Below 450° C, the films were polycrystalline with a strong (111) preferred orientation.

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The method of replication affects metal film granularity and resolution

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100155517 ◽

1989 ◽

Vol 47 ◽

pp. 708-709

Author(s):

George C. Ruben

Keyword(s):

Electron Beam ◽

High Resolution ◽

Film Thickness ◽

Single Molecule ◽

Metal Film ◽

Vertical Surface ◽

High Resolution Imaging ◽

Controllable Factors ◽

Resolution Imaging

Single molecule resolution in electron beam sensitive, uncoated, noncrystalline materials has been impossible except in thin Pt-C replicas ≤ 150Å) which are resistant to the electron beam destruction. Previously the granularity of metal film replicas limited their resolution to ≥ 20Å. This paper demonstrates that Pt-C film granularity and resolution are a function of the method of replication and other controllable factors. Low angle 20° rotary , 45° unidirectional and vertical 9.7±1 Å Pt-C films deposited on mica under the same conditions were compared in Fig. 1. Vertical replication had a 5A granularity (Fig. 1c), the highest resolution (table), and coated the whole surface. 45° replication had a 9Å granulartiy (Fig. 1b), a slightly poorer resolution (table) and did not coat the whole surface. 20° rotary replication was unsuitable for high resolution imaging with 20-25Å granularity (Fig. 1a) and resolution 2-3 times poorer (table). Resolution is defined here as the greatest distance for which the metal coat on two opposing faces just grow together, that is, two times the apparent film thickness on a single vertical surface.

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