abstract:In solid-state physics, heavy fermion materials are a specific type of intermetallic compound, containing elements with 4f or 5f electrons. Electrons are one type of fermion, and when they are found in such materials they are sometimes referred to as heavy electrons.
Our theorycan beappliednot only to thealloysystemsofheavyelectronmetals, but also to the discussion of dopingeffects in newlydiscoveredheavy- fermioninsulators.