Re: Is there a Spin wave of an Electron ?

Hi Birol,

The term spin waves in solid state physics refers to propagating disturbances in the magnetic moments of atoms in a crystal lattice. But your questions here seem to relate instead to electrons orbiting a single atom, and whether or not their 'movement' can be detected as some form of electromagnetic radiation. I'm afraid the answer here is 'no'.

The problem is, your questions are based on the Bohr model of the atom, a solar-system-like model where the negatively charged electrons move in circular orbits around the positively charged nucleus. The model worked well at the time (1913) for describing how atomic spectra worked, and is still a useful approximation for some types of calculations, but suffers from some serious flaws.

To start with, the whole concept of point-like electrons orbiting the nucleus in well-defined circular paths is a classical one, goes against several important principles in modern quantum mechanics. Another objection that relates directly to your question is the problem of cyclotron radiation.

When an electron or other charged particle moves in a curved path, it emits electromagnetic radiation (see the above link), which in turn carries energy away from the particle. If the electrons were actually moving in circular orbits (as the Bohr model says), they would be constantly emitting radiation and losing energy. The electron orbits would quickly decay, and they would end up falling into the nucleus.

So from this, you can draw (at least) two clear conclusions:

• The Bohr model is not an accurate description of how electrons orbit nuclei, and
• If the electron spins or orbits themselves produced detectable electromagnetic radiation, they would lose energy and fall into the nucleus. Since atoms and electron orbitals are stable, they can't be producing 'spin waves' like those you ask about.