EAPSI:Understanding and Controlling the Properties of Magnetic Semiconductor Nanomaterials based on Europium

Rosa Nicholas, Washington DC

Investigators

Abstract

The next generation of electronic devices rests upon two advances in the materials used in their construction: new materials with novel properties and shrinking devices to the nanoscale. Magnetic semiconductors are an exciting but poorly-understood class of materials that display a number of interesting effects desirable for modern electronics applications. In these materials, the electronic, optical, and magnetic properties are highly coupled, leading to a strong interdependence among them. This interdependence allows for control of all of these properties based upon changes in only one. For example, when in a magnetized state, these materials exhibit a large change in their electrical resistance or interaction with polarized light. Understanding how to make these materials and how to control the properties on the nanoscale is an important first step in harnessing them for use in devices from displays to hard drives to processors and quantum computers. For understanding the fundamental properties of magnetic semiconductor nanomaterials, an excellent model system is the europium chalcogenides: oxide (EuO), sulfide (EuS), selenide (EuSe), and telluride (EuTe). All of these materials are indirect bandgap semiconductors that display a range of magnetic behavior from ferromagnetic in EuO and EuS to metamagnetic in EuSe to antiferromagnetic in EuTe. Recently, nanostructures of the europum chalcogenides have been synthesized by the PI?s home research group at Georgetown University and the research group of Yasuchika Hasegawa at Hokkaido University, where the PI will work under this award. These nanostructures are an ideal platform to study the fundamental behavior and coupling exhibited on the nanoscale. Toward this understanding, this project will investigate the synthesis and characterization of cation and anion doped EuS and EuSe nanostructures as a means to control electronic, optical, and magnetic properties by controlling composition. This NSF EAPSI award is funded in collaboration with the Japan Society for the Promotion of Science.