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About Omics Group OMICS GroupOMICS Group International through its Open Access Initiative is committed to make genuine and reliable contributions to the scientific community. OMICS Group hosts over 400 leading-edge peer reviewed Open Access Journals and organize over 300 International Conferences annually all over the world. OMICS Publishing Group journals have over 3 million readers and the fame and success of the same can be attributed to the strong editorial board which contains over 30000 eminent personalities that ensure a rapid, quality and quick review process. OMICS Group
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About Omics Group conferences OMICS Group signed an agreement with more than 1000 International Societies to make healthcare information Open Access. OMICS Group Conferences make the perfect platform for global networking as it brings together renowned speakers and scientists across the globe to a most exciting and memorable scientific event filled with much enlightening interactive sessions, world class exhibitions and poster presentationsOMICS GroupOMICS Group Omics group has organised 500 conferences, workshops and national symposium across the major cities including SanFrancisco,Omaha,Orlado,Rayleigh,SantaClara,Chicag o,Philadelphia,Unitedkingdom,Baltimore,SanAntanio,Dub ai,Hyderabad,Bangaluru and Mumbai.
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Mechanical Effects of Light: Radiation Pressure, Photon Momentum, and the Lorentz Force Law Masud Mansuripur College of Optical Sciences, University of Arizona, Tucson Lasers, Optics & Photonics Conference, Philadelphia, Pennsylvania, September 8, 2014
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Radiation pressure is (partially) responsible for the tails of the comets pointing away from the Sun West (1976) Kohoutek (1974) First suggested by Johannes Kepler in his treatise “De Cometis.” According to this hypothesis the solar ray pressure is responsible for the deflection of the comet tails. Although the observed deflections could not be explained solely on the basis of light pressure, this hypothesis played a significant role in understanding the effect of light pressure in the universe. 2/14 Johannes Kepler (1571-1630)
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Einstein Box “ Thought Experiment” Time of flight = L/c Recoil velocity = p/M Box displacement = (p/M)(L/c) Center-of-mass displacement = ( E /c 2 )L – M (p/M)(L/c) = 0 p = E /c E = mc 2 M Lp 3/14
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Radiation Pressure on Dielectric Wedge EoEo HoHo n B F 4/14 At Brewster’s angle of incidence, where tan B = n, reflectance of the surface for p-polarized light is exactly zero.
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n 1iquid n bead Optical tweezers p in p out F F The first optical traps were built by Arthur Ashkin at AT&T Bell Labs in 1970. "Levitation traps" used the upward-pointing radiation pressure to balance the downward pull of gravity, whereas "two-beam traps" relied on counter- propagating beams to trap particles. Then, in 1986, Ashkin and colleagues realized that the gradient force alone would be sufficient to trap small particles. They used a single tightly focused laser beam to trap a transparent particle in three dimensions. 5/14 Lens
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Circularly-polarized light passing through a half-wave plate z /2-plate L = ( E / )zL = ( E / )z ^ ^ Birefringent crystal (transparent) 6/14
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Collimated beam of light passing through a transparent spiral ramp Emergent beam has (orbital) angular momentum Optical Vortex 7/14
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Spin and Orbital Angular Momentum Circularly polarized beam of light Absorptive particle 8/14
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Feynman Lectures on Physics (Vol. II) 9/14
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V E B q f = q (E + V B) 10/14 Hendrik Lorentz (1853-1928)
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Charge-Dipole Paradox x' y' z' d q x y z V In the moving xyz frame a torque acts on the magnetic dipole. 11/14 In the rest frame x'y'z' there is neither force nor torque acting on either particle.
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The Einstein-Laub Force and Torque Density Equations In the rest frame x'y'z', and also in the moving frame xyz, there is neither force nor torque acting on either particle. 12/14 Albert Einstein (1879-1955)
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Foundations of Classical Electrodynamics 1)There is more to Maxwell’s macroscopic equations than meets the eye. Take them seriously. Make them the starting point of every investigation in classical electrodynamics. 2)The most important thing you will need to know about EM energy is that the Poynting vector S(r, t) = E H is the rate of flow of energy (per unit are per unit time). Everything else about energy follows from this postulate in conjunction with Maxwell’s macroscopic equations. 3)Momentum density of EM fields is p(r, t) = S/c 2. This is always true, in vacuum as well as in material media, irrespective of the nature of the media. 4)Angular momentum density of EM fields is always L(r, t) = r S/c 2. This is true of spin as well as orbital angular momentum of EM waves. 5)If you use the Lorentz force law f = q(E + V B), you will get into trouble: you will find that momentum is not conserved and special relativity is violated. Use the Einstein-Laub law instead! 14/14
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Maxwell’s macroscopic equations (SI) D = free × H = J free + D/ t × E = B/ t · B = 0 Electric displacement D is related to polarization density P: D = o E + P = o (1+ e )E = o E Magnetic induction B is related to magnetization density M: B = o H + M = o (1+ m )H = o H free, J free, P, and M (r, t) are the sources of radiation E(r,t) and H(r,t) are the radiated fields Exact equations (mathematically). No small-scale averaging required. Reducible to microscopic equations. 15/14 James Clerk Maxwell (1831-1879)
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Hidden Momentum p hidden = o M E o IoIo · m o = o I o A z ^ ^ z Point charge + EoEo EoEo x y+ S hidden = M E o / o 16/14 William Shockley (1910-1989)
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Let Us Meet Again We welcome all to our future group conferences of Omics group international Please visit: www.omicsgroup.com www.Conferenceseries.com http://optics.conferenceseries.com/
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