The energies of the two states of the electron are different in a magnetic field. Isn't the absorption then of radiation in transition between them electron spin resonance? It is routinely measured in atoms or molecules with unpaired electrons.I dont believe that the electron really spins but why would it radiate? the field isnt changing.
http://physicsworld.com/cws/article/news/27794Although the theory that frozen helium might be a supersolid has been around for years, the first evidence that it was at least a super-something was provided in a 2004 experiment by Moses Chan at Penn State. Researchers there placed a tiny cylinder of frozen helium in a torsion oscillator, which rotates rapidly forward and back, like a washing machine agitator. The resonant frequency of the oscillator -- the one it naturally settles into -- depends on the mass it's trying to move around and back. The researchers found that below a critical temperature, some of the mass of the (solid) helium seemed to disappear.
Physicists in the US have shown that a supposed quantum phase of matter known as a "supersolid" is strongly dependent on the amount of crystal disorder present in the sample being studied. By performing experiments on samples of helium-4 with large amounts of disorder, they found that the trademark effects of supersolidity in the samples rose to more than 20% -- by far the largest proportion seen so far.