Quantum confinement in EuO heterostructures

Quantum wells are created from ultrathin single-crystalline EuO layers to study the evolution of the opticalband gap down to the single nanometer regime. We find that the EuOband gap is indirect —independent ofquantum well thickness —and increases from 1.19 eV for bulk-like (d = 32 nm) to ≈1.4 eV in the ultrathin films (d = 1.1 nm). The observedband-gap widening is a clear sign of a quantum confinement effect, which can be used to control and modify theband gap in EuO-based all-oxideheterostructures.

Source: Applied Physics Letters - November 14, 2016 Category: Physics Authors: G ünther M. Prinz, Timm Gerber, Axel Lorke and Martina Müller Source Type: research