[Q] Do photons produce a magnetic field?

[n00b]

Light is part of the electromagnetic spectrum. Photons can excite photovoltaic cells to produce electricity. Can photons produce a measurable magnetic field?

[Qfwfq]

There are no magnetic monopoles, so it can't be done the same way as the photovoltaic effect.

 

Circular polarized photons can flip the angular momentum state of things in a material; this implies also flipping the associated magnetic dipole moment and it happens for instance in NMR under a strong external magnetic field and requires a kind of tuning. I don't know of any phenomena of a macroscopic magnetic field being produced where there is none already, though I can't rule out it being somehow possible.

[Doctordick]

Light is part of the electromagnetic spectrum. Photons can excite photovoltaic cells to produce electricity. Can photons produce a measurable magnetic field?

Photons are electro-magnetic fields: i.e., one of the solutions of Maxwell's equations. If you have enough of them, they certainly can produce a "measurable" magnetic field; common everyday radios detect the existence of changing electric and magnetic fields by simply amplifying the effect via resonence in the circuits! Oh yeah, radio waves are just huge collections of very low energy but coherent photons.

 

Have fun -- Dick