Photomagnetic effect

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The photomagnetic effect is a theoretical quantum mechanical effect discovered by the researchers Samuel L. Oliveira and Stephen C. Rand at University of Michigan 2007–2011. [1] [2] [3] [4] The researchers have discovered a powerful magnetic interaction between the photons dynamic magnetic field – and certain isolator materials atoms magnetic moment, that is 100 million times stronger than formerly anticipated. Under the proper circumstances, the photons magnetic fields effect is as strong as their electric field – as e.g. in solar cells.

The discovery is a surprise, because it is not straightforward to derive the strong magnetic effect from the physical equations, and thereby indicate that this quantum mechanical effect would be interesting enough. That is why the photomagnetic effect has been neglected for more than 100 years.

The researchers have theoretically calculated that incoherent light as e.g. sunlight, is almost as efficient as laserlight, to be converted by the photomagnetic effect.

In 2011 the power density should be 10 million watt per square centimeter, but the researchers will look for new photomagnetic materials, that can work with lower light intensities.

It could make solar energy-to-electric energy conversion cheaper than today, but considering that a polycrystalline photovoltaic cell forms only 30–40% of the total price of a solar panel, it may not be economically advantageous, so the main factor will be a dependence on the raw materials, some of which, Indium as an example, has known sources to last less than 2 decades at current exploitation rate. Indium is used in many types of current photovoltaic solar panels.

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References[edit]

  1. ^ April 13, 2011, ns.umich.edu: Solar power without solar cells: A hidden magnetic effect of light could make it possible
  2. ^ University of Michigan (2011, April 14). Solar power without solar cells: A hidden magnetic effect of light could make it possible. ScienceDaily Quote: "..."You could stare at the equations of motion all day and you will not see this possibility. We've all been taught that this doesn't happen," said Rand, an author of a paper on the work published in the Journal of Applied Physics. "It's a very odd interaction. That's why it's been overlooked for more than 100 years."..."
  3. ^ Apr 21, 2011, physicsworld.com: Solar power without solar cells
  4. ^ Subscription needed: J. Appl. Phys. 109, 064903 (2011); doi:[http://dx.doi.org/10.1063%2F1.3561505 10.1063/1.3561505, published online 21 March 2011: Optically-induced charge separation and terahertz emission in unbiased dielectrics] pdf Quote: "...A magneto-electric power generation scheme has been proposed that relies on displacement currents in insulators, and avoids both the absorption and the electron-hole pair production that typify semiconducting solar cells...", (referred reference: Phys. Rev. Lett. 98, 093901 (2007), doi:[http://dx.doi.org/10.1103%2FPhysRevLett.98.093901 10.1103/PhysRevLett.98.093901: Intense Nonlinear Magnetic Dipole Radiation at Optical Frequencies: Molecular Scattering in a Dielectric Liquid] Quote: "...Large magnetic response is very unexpected at optical frequencies, and should lead to the discovery of new magneto-optical phenomena and the realization of low-loss homogeneous optical media with negative refractive indices...")