Contact Hyperfine Interactions in Semiconductor Heterostructures

Nuclear spins interact with surrounding electrical environment and electron spins interact with surrounding nuclear spin environment. These interactions lead to a small shift and/or splitting of energy levels and are called hyperfine interactions. Especially, contact hyperfine interaction between nuclei and conductive carriers plays an essential role in manipulating nuclear spins (electron spins). Understanding and precise control of contact hyperfine interaction provide us with new possibilities to establish a highly sensitive nuclear magnetic resonance (NMR) and a coherent control of small quantity of nuclear spins in semiconductor hetero- and nanostructures. In this chapter, fundamental features of contact hyperfine interaction are overviewed together with related phenomena, such as electrical (optical) control, NMR based on hyperfine interactions, and coherent control of nuclear spins.