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Potential mapping of optical tweezers
Optics Letters, 2011Optical tweezers are very often used for measurement of piconewton range forces. Depending on the displacement of the trapped bead, the trap may become stiffer which causes considerable underestimation of the measured force. We have shown, both by theory and experiment, that such a stiffening occurs for beads larger than 0.5 μm in radius. For the first
Tahmineh, Godazgar +2 more
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Journal of Mathematical Physics, 1986
The possibility of confining a quantum particle in an optical potential, the imaginary part of which would be related to the existence of inelastic reaction channels coupled to the elastic one, is considered. Pure imaginary potentials of various (constant, linear, and parabolic) radial shapes are studied.
F. J. Gomez, M. F. Rañada, J. Sesma
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The possibility of confining a quantum particle in an optical potential, the imaginary part of which would be related to the existence of inelastic reaction channels coupled to the elastic one, is considered. Pure imaginary potentials of various (constant, linear, and parabolic) radial shapes are studied.
F. J. Gomez, M. F. Rañada, J. Sesma
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On the theory of the optical potential
Annals of Physics, 1969Abstract We consider elastic scattering of a projectile by a complex many-body system. The incident energy is assumed high enough so that closure may be used on the target, and the problem is reduced to computing the target ground-state expectation value of the scattering amplitude from A fixed scattering centers.
L.L Foldy, J.D Walecka
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Optical measurement of membrane potential
1978Optical measurement of membrane potential is a new tool for physiologists and has already found many applications. However, the number of possible pitfalls is alarming, particularly in situations where comparison with electrode measurements is impossible.
L B, Cohen, B M, Salzberg
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Optical probes of membrane potential
The Journal of Membrane Biology, 1976There are two basically different mechanisms for the fluorescence and absorption changes of merocyanine, cyanine and oxonol dyes. The permeant dyes (cyanine and oxonol dyes, with delocalized charges) work by a potential-dependent accumulation mechanism. These dyes show large (up to 80%) fluorescence and absorption changes with suspensions of cells, and
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Optical MEMS potentials in optical storage
1998 IEEE/LEOS Summer Topical Meeting. Digest. Broadband Optical Networks and Technologies: An Emerging Reality. Optical MEMS. Smart Pixels. Organic Optics and Optoelectronics (Cat. No.98TH8369), 2002To compete with this steady increase in capacity and performance at relatively fixed cost, new approaches are being pursued to increase the capacity and performance of optical disk storage products. Micromachining technologies will play an important role in these new systems.
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Reports on Progress in Physics, 1984
The nucleon optical model is described, with particular reference to the analysis of neutron scattering and reaction cross sections. The central, spin-orbit and isospin terms in the potential are defined and the results of phenomenological determinations of their parameters reviewed.
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The nucleon optical model is described, with particular reference to the analysis of neutron scattering and reaction cross sections. The central, spin-orbit and isospin terms in the potential are defined and the results of phenomenological determinations of their parameters reviewed.
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On the imaginary optical potential
Nuclear Physics, 1959Abstract The imaginary part of the nuclear optical potential for nucleons is investigated in a semi-quantitative way. For simplicity, harmonic oscillator wave functions have been used to perform calculations for O16 and Ca40. Results indicate that surface absorption is quite important for incident energies up to about 60 MeV.
R.H. Lemmer, Th.A.J. Maris, Y.C. Tang
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Nuclear Physics A, 1974
Abstract We use the impulse approximation, the Tabakin internucleon potential and a Fermi gas model for the nucleus to calculate the low energy nucleon-nucleus optical potential. The real and imaginary parts are calculated simultaneously but it is found to be an extremely good approximation to calculate them separately as is usually done.
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Abstract We use the impulse approximation, the Tabakin internucleon potential and a Fermi gas model for the nucleus to calculate the low energy nucleon-nucleus optical potential. The real and imaginary parts are calculated simultaneously but it is found to be an extremely good approximation to calculate them separately as is usually done.
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Optical potential for deuteron
Nuclear Physics A, 1969Abstract An analytical expression for the deuteron optical potential is used to calculate the differential cross section for the elastic scattering of the deuteron from various targets. Comparison with experimental results indicates that a good fit to the experimental results cannot be obtained if the well-depth of the imaginary part of the nucleon ...
R.K. Satpathy +2 more
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