Department of Applied Physics and Materials Science - Materials Science

Research

We seek to understand and control the world of solids, liquids, and gases around us. Traditional materials science has a focus on "engineering materials" of technological importance such as ion conductors or doped silicon. At Caltech we also develop engineering materials and devices as we see opportunities, but we also try to control the stability of crystals under pressure or temperature, for example. A rigorous emphasis on basic science and mathematics backs up what we do.

Research Groups

Harry Atwater daedalus.caltech.edu

Professor Harry Atwater's group is engaged in fundamental and applied research in the synthesis, properties and processing of electronic materials for use in the electronic and opto-electronic devices and circuits of the 21st century. Electronic materials research is interdisciplinary, involving challenges in applied physics, physics, materials science, electrical and chemical engineering. The members of the Atwater group includes graduate students, research fellows and undergraduates from each of these departments. They also maintain comprehensive experimental facilities for growth and analysis.

Kaushik Bhattacharya www.mechmat.caltech.edu

The research activities of Kaushik Bhattacharya are at the intersection of Mechanics, Materials Science and Applied Mathematics. Concepts in Mechanics and recent methods of Mathematics are used to generate ideas for the design, development, and creation of new materials and the optimization of materials processing.

Katherine Faber faber.caltech.edu

Katherine Faber is interested in the fracture of brittle materials and mechanisms by which such materials can be toughened and strengthened through composite strategies and residual stresses, often using synchrotron radiation for internal stress measurement. Her studies comprise ceramics for energy-related applications including thermal and environmental barrier coatings for power generation components and porous solids for filters and flow. More recently, she has also worked with the Art Institute of Chicago to establish the Northwestern University/Art Institute of Chicago Center for Scientific Studies in the Arts where advanced materials characterization and analytical techniques are used in support of conservation science.

Brent Fultz www.its.caltech.edu/~matsci/btfgrp/BTF_Group1.html

Professor Fultz and his group work broadly in the areas of materials science, with emphasis on metals physics, thermodynamics, and kinetics. Experimental work employs elastic and inelastic scattering of neutrons, x-rays, gamma-rays, and electrons. Applied research projects include the development of new materials for electrodes in rechargeable batteries, and rare-earth alloys with giant magnetostriction.

Bill Goddard www.wag.caltech.edu

Professor Goddard's research group is the Materials and Process Simulation Center (MSC), located in the Beckman Institute at the California Institute of Technology. This multidisciplinary center (with ~50 graduate students and postdoctoral fellows having expertise in chemistry, materials science, physics, engineering and biotechnology) focuses on the theoretical methods of Quantum Mechanics and molecular dynamics for first principles predictions of the fundamental structures, properties, reactivity, and processing of materials with applications ranging from metal alloys, semiconductors, and ceramics to polymers, proteins, DNA, carbon nanostructures. Current focus is on fuel cells (membranes and catalysts), nanoelectronics, catalysis, and biotechnology plus various materials projects funded directly by industry. He is also director for the Power, Environmental, and Energy, Research (PEER) Center (located off-campus) with a staff of ~20 experimentalists studying problems in petroleum, energy, and environmental technologies.

Julia R. Greer www.jrgreer.caltech.edu

The main focus in Professor J.R.Greer's research group is on investigating nano-scale material properties. Specifically, we have developed a unique fabrication technique involving the use of Focussed Ion Beam (FIB) to "carve out" single crystal nanopillars ranging in diameter from 100 nm to several microns. Their strengths in uniaxial compression are subsequently measured in the Nanoindenter with a flat punch tip to remove the strain gradient effect from the observed mechanical response. These small pillars exhibit a very strong size effect in FCC and BCC crystals, i.e. smaller pillars are some 50x stronger than bulk, with the strengths at a significant fraction of the ideal shear strength. The group’s efforts are currently concentrated on the development of an in-situ mechanical testing instrument called the "SEMentor" which combines the strengths of two instruments: SEM and the Nanoindenter, allowing for direct visualization of mechanical deformation during testing, local electron beam irradiation, and beyond-compression testing (i.e. tension). The following broad topics are currently available for graduate student research:

  1. Mechanical property evolution during mechanical deformation of nano-scale crystals and metallic glasses in tension and compression.
  2. Dislocation behavior in nano-scale crystals through experiment and computations.
  3. Investigation of local electron irradiation effects on the bandgap and electrical performance of nano-scale semiconductors (i.e. graphene ribbons)

Thermoelectric Materials and Engineering thermoelectrics.caltech.edu

The Caltech Thermoelectrics group focuses on developing high-efficiency materials for thermoelectric power generation. Thermoelectrics have powered NASA deep space probes for decades. At Caltech we are developing thermoelectric materials for sustainable energy on Earth, for example, by converting waste heat from the exhaust in an automobile to electricity that will recharge the battery. At Caltech, thermoelectrics students can learn a variety of techniques: 1) Solid State Chemistry to synthesize compounds with complex crystal structures, 2) Materials Science and Engineering to develop processing that produces nanostructured composites, 3) Solid State Physics to understand and model the various thermoelectric properties, and 4) thermoelectric engineering to design new systems. Caltech thermoelectrics shares group meetings and lab space with students often work with the facilities and thermoelectrics scientists at the Jet Propulsion Laboratory.

William Johnson www.its.caltech.edu/~vitreloy

Professor Johnson's group does research on non-equilibrium and metastable materials. During the past decade, they have developed unusual metallic alloys which fail to crystallize during solidification at low cooling rates, thus forming "bulk" glasses. Research on the liquid alloys includes fundamental studies of rheology, atomic diffusion, crystallization kinetics, liquid/liquid phase separation, and the glass transition. Research on the solid "glassy" materials includes studies of elastic properties, and mechanisms of deformation, flow, and fracture. The group has developed composite materials which employ a metallic glass matrix to achieve unusual combinations of properties for structural engineering applications.