Electrons Trapped in Solid Neon–Hydrogen Mixtures Below 1K

Abstract

We report on an electron spin resonance study of electrons stabilized in solid films of neon–hydrogen mixtures. We found that these films are highly porous and may absorb large amount of liquid helium. We observed that free electrons can be stabilized in two different positions: in a pure neon environment and in H 2 clusters formed in the pores of solid neon. It turned out that the presence of the superfluid helium film suppresses the escape of the trapped electrons via diffusion through the pores and stimulates their accumulation in the H 2 clusters even in Ne samples of the best available purity. We propose several possible explanations for this behavior.