Inducing current with magnetic field from light

[saime]

Hey everybody,

I was wondering if one could use the magnetic fields of light to induce an electrical current, even if it was just a small one. I'm not talking about the use of photovoltaic cells, but the actual magnetic fields of light.

Thanks

 

[ZapperZ]

In accelerating structures, the EM wave in the cavity induces wall currents due to the changing E and B field, depending on the modes/geometry of the field. So having induced current due to EM radiation is rather common.

Zz.

 

[UltrafastPED]

Yes, it has been done with light, using high powered ultrafast lasers. The term used in plasma physics is "ponderomotive force"; see http://farside.ph.utexas.edu/teaching/plasma/lectures/node26.html

Note that the final expressions are in terms of the electric field, but the derivation uses Faraday's law to "convert" the rid the expression of the B field.

The ponderomotive force is used with high-powered ultrafast lasers to create table-top particle accelerators:
http://www.colorado.edu/physics/phys7810_005/phys7810_005_fa09/articles/Malka_NaturePhys_2008.pdf

This was first done about 2004; some of the work was done across the hall from my lab:
http://accelconf.web.cern.ch/accelconf/IPAC10/papers/thpec011.pdf

 

[Vanadium 50]

Note that this is exactly what happens in a radio - just with lower frequencies of light.

 

[saime]

Thanks for the answers everyone.