Solid State Research

This program has several purposes:

Optimizing properties for a particular application-maximizing the carrier mobility in a semiconductor multilayer structure, achieving a high-critical current in an oxide superconductor, or designing and preparing a new type of conducting polymer-is a key part of the solid state research. For example, in the case of electrical transport in semiconductors, the issues might include where the carriers originate, what governs their mobility, and how they travel form one substance to another across interfaces.

Various properties of semiconductor materials are under study-their structure, optical reflection or absorption, heat capacity, transport properties and magnetic properties. Materials under investigation include high-transition temperature superconductors, heavy Fermion conductors, and conducting polymers. Other research topics include the study of noise processes in semiconductor materials and devices, growth and characterization of nanoparticles, properties of quantum wires and dots, and the study of amorphous glasses or crystalline ceramics from soft (sol gel) processing.

The program includes both theoretical studies and experimental investigations. The theoretical studies are intended to develop a fundamental understanding of the properties of solid state and luminescent materials and to develop the ability to make accurate predictions of these properties, starting from first principles. In the experimental investigation, materials are prepared (e.g., by thin film deposition, crystal growth, or preparation of a composite) and interesting physical properties or qualities are measured and compared to predictions.

A variety of experimental techniques and equipment are available for studying solid-state materials: the ability to make resistance measurements from extremely low temperatures (fractions of milliKelvin) to high temperatures (1,000°C), infrared and optical characterization, microwave response, magnetic resonance, heat capacity, magnetic susceptibility, crystal structure, ion channeling and backscattering, and an array of surface spectroscopies.

Materials are prepared in a variety of forms, particularly in thin films, using techniques that include molecular beam epitaxy and laser-assisted growth. Metals, insulators and semiconductors are prepared, often using electron beam systems, sputtering, or thermal evaporation. Various chemical synthesis techniques may be used for composite and nanostructured materials.

Participants from all five departments involved in MICROFABRITECH are taking part in this program.

Some examples of current research: