Kvantdefekt

Kvantdefekt is a term used in condensed matter physics to describe the deviation of the local electronic environment around an impurity atom in a solid from that of a free atom. This effect arises from the interactions between the impurity's electrons and the electrons of the surrounding host lattice. Specifically, the presence of the host's electrons can screen the nuclear charge of the impurity, leading to a change in the effective potential experienced by the impurity's valence electrons. This screening can alter the energy levels, magnetic moments, and other properties of the impurity compared to its free atomic state.

The concept of kvantdefekt is particularly relevant when studying magnetic impurities in metals. The conduction electrons of the host metal can interact with the localized magnetic moment of the impurity, leading to phenomena like the Kondo effect. The degree of kvantdefekt is influenced by factors such as the impurity species, the host material, and the local atomic arrangement. Understanding kvantdefekt is crucial for predicting and explaining the behavior of dilute magnetic alloys and other systems where impurity properties are of interest. It represents a fundamental aspect of how electronic structure is modified when an atom is embedded within a solid.