Optical: systems and elements – Light interference – Produced by coating or lamina
Reexamination Certificate
2001-12-28
2003-12-09
Juba, John (Department: 2872)
Optical: systems and elements
Light interference
Produced by coating or lamina
C359S580000, C359S900000, C250S526000
Reexamination Certificate
active
06661576
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates to an apparatus and method for controlling the behavior (repulsive or attractive) and magnitude of dispersion forces, such as the Casimir force.
BACKGROUND OF THE INVENTION
Quantum field theory predicts, and experimentation has confirmed, that two, parallel, neutral (i.e., not electrically charged) planar slabs of any material that are separated from one another give rise to a mutually attractive force. This force is usually called the Casimir force after the theorist that postulated its existence in 1948.
The Casimir force is due to the perturbation, caused by the slab boundaries, on the random oscillations (due to Heisenberg's uncertainty principle) of the electromagnetic field. In the region of space that is not between the slabs, the values of the electric and magnetic fields can freely fluctuate. But in the region of space that is between the slabs, the modes of oscillation of the electric and magnetic fields are restricted. Consequently, a gradient arises wherein the energy density in the region that is not between the slabs is greater than the energy density in the region between the slabs. This gradient is ultimately responsible for the Casimir force.
Most theoretical analyses have treated the Casimir force as an attractive force. But it has been suggested that, under certain circumstances, the Casimir force might manifest as a repulsive interaction. This is a consequence of the symmetry of the Maxwell equations under appropriate exchanges of the electric and magnetic fields. In particular, it has been predicted that the Casimir force between a perfectly conducting and a perfectly magnetically permeable material is repulsive. While this prediction has not been tested experimentally, it is based on the same body of evidence that has produced all the predictions about the Casimir force that have been verified to date.
In a recent treatment, the Casimir force is considered to be the net force that results from the contribution of each of an infinite number of spectral (i.e., frequency/wavelength) components. See Ford, L. H., “Spectrum of the Casimir Effect and the Lifshitz Theory,” Phys. Rev. A, vol. 48, no. 4, p 2962 (1993), incorporated by reference herein. By analyzing the oscillations that comprise the Casimir force on a frequency-by-frequency basis, the contribution of each frequency to the total Casimir force can be determined. According to this work, the Casimir force appears to be the net result of a “near” exact cancellation of forces at all frequencies, all of which forces are much larger than the net force (i.e., the resulting Casimir force).
A question arises as to whether or not it is possible to controllably alter this infinite sum of terms. If it is possible, for example, to include only the “attractive” contributions or only the “repulsive” contributions, then the “sign” or “behavior” (i.e., repulsive or attractive) of the Casimir force can be controllably determined. Furthermore, if the contributions can be manipulated in this manner, then, in principle at least, the magnitude of the force can be increased without limit. See, Ford, L. H., “Casimir Force Between a Dielectric Sphere and a Wall: A Model for Amplification of Vacuum Fluctuations,” Phys. Rev. A, vol. 58, no. 6, p. 4279 (1998), incorporated by reference herein.
Until now, no one has identified a system of two parallel plates that allows for the isolation of certain contributions while suppressing all others. This has been attributed to the fact that materials cannot be devised (due to fundamental physical reasons relating to causality) whose bulk properties display the necessary optical characteristics.
SUMMARY OF THE INVENTION
In accordance with the present teachings, the behavior and magnitude of a dispersion force is controllably altered by allowing the propagation of only those spectral components (i.e., frequencies) at which the random oscillations of the electromagnetic field contribute to the force behavior desired, while substantially suppressing all other spectral components.
In one embodiment, selective retention/suppression of spectral components is achieved by disposing two elements in spaced relation to one another. At least one of the elements comprises at least one periodic structure that is advantageously capable of achieving omni-directional selective reflection of selected spectral components. In some embodiments, such omni-directional selective reflection is obtained using photonic band gap material.
In embodiments in which the dispersion force is controllably altered to exhibit a repulsive force, the elements will repel each other. Consequently, in some embodiments wherein one of the elements is restrained from movement, the other element will “float” above it. The ability to control dispersion forces as described herein has many important applications in the areas of telecommunications, transportation, and propulsion, to name but a few.
REFERENCES:
patent: 2002/0135877 (2002-09-01), Fan et al.
patent: 3541084 (1987-08-01), None
patent: 2276488 (1994-09-01), None
patent: 2283611 (1995-05-01), None
patent: 2325778 (1998-08-01), None
patent: 2352320 (2001-01-01), None
T.V. Prevenslik, “The Casimir Force—Neutral or Electrostatic?” ESD Journal, Feb. 10, 2003, www.esdjournal.com/techpapr/prevens/casimir/casimir.htm.*
Astrid Lambrecht, “The Casmir effect: a force from nothing”, Physics World Sep. 2002, http://physicsweb.org/article/world/15/9/6.*
Eyal Buks and Michael L. Roukes, “Quantum physics: Casimir force changes sign”, Nature 419, Sep. 12, 2002, pp. 119-120.*
O. Kenneth, et al., “Repulsive Casimir Forces”, Physical Review Letters, vol. 89, No. 3, 033001, Jul. 15, 2002.*
F. Chen and U. Mohideen, “Demonstration of the Lateral Casimir Force”, Physical Review Letters, vol. 88, No. 10, 101801, Mar. 11, 2002.*
H.B. Chan, et al., “Quantum Mechanical Actuation of Microelectromechanical Systems by the Casimir Force”, Science vol. 291, pp. 1941-1944, Mar. 9, 2001, with corrections.*
E. Buks and M.L. Roukes, “Stiction, adhesion energy, and the Casimir effect in micromechanical systems”, Phys. Rev. B, vol. 63, No. 3, 033402, Jan. 15, 2001.*
D.N. Chigrin, et al., “All-Dielectric One-Dimensional Periodic Structures for Total Omnidirectional Reflection and Partial Spontaneous Emission Control”, J. Lightwave Techn., vol. 17, No. 11, pp. 2018-2024, Nov. 1999.*
P.St.J. Russell, et al., “Full photonic bandgaps and spontaneous emission control in 1-D multilayer dielectric structures”, CLEO '99, CThK12, p. 405, May 27, 1999.*
L.H. Ford, “Spectrum of the Casimir effect and the Lifshitz theory”, Phys. Rev. A vol. 48, No. 4, pp. 2962-2967, Oct. 1993.*
H.B. Chan, et al., “Nonlinear Micromechanical Casimir Oscillator”, Phys. Rev. Lett., vol. 87, No. 21, 211801, Nov. 19, 2001.*
Timothy H. Boyer, “Van der Waals forces and zero-point energy for dielectric and permeabl materials”, Phys. Rev. A vol. 9, No. 5, pp. 2078-2084, May 1974.*
Gerald Feinberg, “General Theory of the van der Waals Interaction: A Model-Independent Approach”, Phy. Rev. A vol. 2, No. 6, pp. 2395-2415, Dec. 1970.*
U. Mohideen and Anushree Roy, “Precision Measurement of the Casimir Force from 0.1 to 0.9 &mgr;m”, Phys. Rev. Lett., vol. 81, No. 21, pp. 4549-4552, Nov. 23, 1998.*
Xin-zhou Li, et al., “Attractive or repulsive nature of the Casimir force for rectangular cavity”, Phys. Rev. D, vol. 56, No. 4, pp. 2155-2162, Aug. 15, 1997.*
S.J. van Enk, “Casimir torque between dielectrics”, Phys. Rev. A, vol. 52, No. 4, pp. 2569-2575, Oct. 1995.*
P. St. J. Russell, et al., “Full photonic bandgaps and spontaneous emission control in 1D multilayer dielectric structures”, Optics Comm. 160, pp. 66-71, Feb. 1, 1999.*
J. Winn, et al., “Omnidirectional reflection from a one-dimensional photonic crystal”, Optics Lett., vol. 23, No. 20, pp. 1573-1575, Oct. 15, 1998.*
Y. Fink, et al., “A Dielecric Omnidirectional Reflector”, Science 282, 5394 pp. 1679-1682, Nov. 27, 1998.
DeMont & Breyer LLC
Juba John
LandOfFree
Method and apparatus for controlling dispersion forces does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and apparatus for controlling dispersion forces, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for controlling dispersion forces will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3136664