The study of excitons in semiconductors has been an active field of research for many years. Their signature, which dominates the near-bandgape optical properties of semiconductor heterostructures, can be manipulated via external fields or through engineering of the crystal structure, giving rise to a wealth of physical phenomena. Their equivalence with hydrogen atoms was found to hold beyond the single neutral atom.
Theory predicts that at densities, which are well above the Mott transition, the exciton system may form a liquid. At very low temperature and densities one expects to form a Bose condensate, while at higher temperatures and densities – a classical liquid. Our goal is to observe these correlated states in coupled quantum wells structures.