MIT
Reports to the President 1994-95
In September of 1994, the Center for Materials Science and Engineering (CMSE)
at MIT was awarded one of the first National Science Foundation Grants under
the new Materials Research Science and Engineering Center (MRSEC) program.
After a year-long competition that began with more than 100 contestants, CMSE
won the largest of the 11 grants creating new Centers at universities
throughout the nation. We describe below the mission of CMSE and the methods
used to reach its goals, which were applauded by the NSF's mail and panel
reviews.
MIT has an extraordinarily strong and broad effort in materials science and
engineering involving approximately 110 faculty members in 11 departments in
the schools of science and engineering. Several centers and laboratories at
MIT have been established to facilitate industrial participation in such
research. There is great opportunity in this environment to solve problems
that address the needs of society more effectively by encouraging
collaboration. Thus, CMSE has a special mission: to foster collaborative
interdisciplinary research and education in the fundamental science of
materials and in the engineering of materials for specific applications. CMSE
not only promotes collaboration among MIT faculty trained in different
disciplines, but also between MIT researchers and the researchers of other
universities, industry, and government and nonprofit laboratories.
Collaborative research is encouraged through several mechanisms:
interdisciplinary research groups (IRGs), shared experimental facilities
(SEFs), infrastructure enhancement, and outreach programs. The IRGs, described
below, are composed of MIT faculty who, with their students and postdoctoral
associates, wish to investigate fundamental scientific questions and pathways
to reach significant technological goals that can only be properly explored in
a collaborative, multidisciplinary mode. These problems are too large in scope
to be addressed by individual faculty members and their students.
Collaboration is essential for materials-related science and engineering, even
for individual investigators, because such research requires very sophisticated
equipment and infrastructure. CMSE provides a mechanism for the purchase and
supervision of such equipment in its SEFs. The equipment is made available to
the members of the IRGs, individual MIT investigators, and researchers from
other university, industrial, government, and nonprofit laboratories. In these
facilities, students, postdoctoral associates, and industrial researchers
working on different topics intermingle and transfer expertise and technology
across traditional disciplinary boundaries. CMSE also supervises the operation,
maintenance, and improvement of the Vannevar Bush building, thus providing the
infrastructure necessary for first class materials research. Researchers from
four departments are intermixed in the building, facilitating interdisciplinary
cooperation.
In preparation for the competition for MRSEC grants, proposals for new IRGs
were stimulated by notifying members of the MIT materials community early in
1993. After an initial screening of 12 group proposals, eight were subjected
to detailed review by the Internal Advisory Committee (IAC) and by other
knowledgeable MIT faculty, and each of the eight were also reviewed by at least
two referees from outside MIT. The internal and external referees were asked
to rate the proposal with regard to five criteria: the past research
performance of the senior investigators, the likelihood of important scientific
results from the proposed research, the coherence of the IRG, the
interdisciplinary quality of the IRG, and the potential technological impact of
the research. Five of the groups were rated excellent and were included in the
proposal. Each IRG was also reviewed by a new CMSE Science and Engineering
External Advisory Board (SEEAB).
CMSE also provides seed funds. While preference is given to young faculty,
CMSE uses these funds to support research that has the potential of redefining
the direction of an existing IRG or leading to the creation of a completely new
IRG. Seed funding provides CMSE with the flexibility necessary to initiate
high-risk research. During the past year CMSE held an open competition for
seed grants. Proposals were solicited from all junior faculty in the
departments of Aeronautics and Astronautics; Chemical Engineering; Chemistry;
Civil and Environmental Engineering; Electrical Engineering and Computer
Science; Earth, Atmospheric, and Planetary Sciences; Materials Science and
Engineering; Mechanical Engineering; Nuclear Engineering; Ocean Engineering;
and Physics. Nineteen proposals were submitted, of which nine were funded.
Recipients of seed funding included four women. Past seed funding has led to
the founding of several start-up companies that provide more than 100 jobs,
demonstrating both the importance of seed funding and the value of basic
research in creating wealth.
The purpose of this program is to explore the fundamental nature, synthesis,
and properties of Photonic Band Gap (PBG) materials and to exploit these
properties for the creation and control of electromagnetic radiation. These
materials are a composite of a periodic array of macroscopic dielectric
scatterers in a homogeneous dielectric matrix. A PBG material affects the
properties of traveling electromagnetic waves in much the same way that a
crystal of atoms affects the properties of electron waves. Consequently,
photons in PBG materials can have band structures, gaps, localized defect
modes, and surface modes. By allowing the trapping, localization, and
channeling of light with very low loss, these new materials have the potential
of completely revolutionizing the basic elements of photonic and optoelectronic
integrated circuits. The bending radius of a conventional planar waveguide is
limited to 1 cm by scattering losses; this geometry is incompatible with
integrated photon distribution on a chip. A PBG material will allow a 10 mm
radius bend, and provide a gateway to microphotonics. The research addresses a
broad range of fundamental issues in novel synthesis pathways for inhomogeneous
microstructures, new photonic phenomena, and components for well-defined
systems applications. The group has already fabricated and begun to
characterize a one-dimensional PBG waveguide with a bandgap centered at 5 um,
composed of a set of colinear air holes in Si.
Participating faculty and departmental affiliations: Professors H. A. Haus, E.
P. Ippen, L. A. Kolodziejski, and L. R. Reif (Electrical Engineering and
Computer Science); E. R. Brown (Lincoln Laboratory); L. C. Kimerling (Materials
Science and Engineering); and J. D. Joannopoulos (Physics).
The objective of this group is to develop the chemistry and molecular-level
processing needed to control and manipulate the molecular and supermolecular
organizations of macromolecular systems with novel electrical and optical
properties. The development and utilization of combined
molecular/supermolecular engineering schemes will make it possible to design
and fabricate complex, multiphase or multicomponent systems with controllable
molecular architectures and well-defined morphological arrangements. Thus, it
will be possible to create multi-component systems in which each component
serves a well-defined function and is molecularly positioned to achieve a
specific and tunable electrical, optical, or chemical response. The
juxtaposition of different components, such as semiconductor nanocrystallites
and conjugated polymers, may result in new and useful electronic and optical
behavior. Applications of interest include highly anisotropic electrically
conducting films, photonic devices, periodic dielectrics, and thin film
electroluminescent and energy storage devices. For example, the group has
recently fabricated green and blue light emitting diodes using conducting
polymers and polymer/semiconductor-nanocrystal heterostructures.
Participating faculty and departmental affiliations: Professors R. E. Cohen
(Chemical Engineering); M. Bawendi, R. R. Schrock, and R. J. Silbey
(Chemistry); and M. F. Rubner and E. L. Thomas (Materials Science and
Engineering).
Cooperative behavior in the presence of frozen-in randomness, i.e. ordering in
the presence of quenched disorder, permeates all of materials science. Whereas
phase changes in perfect systems are well-understood, the disorder challenges
our ability to understand even qualitative effects and to make precise
predictions and measurements. Cooperative phenomena in the presence of
quenched randomness may also underlie fundamental mechanisms of life sciences
and have applications to information sciences in, for example, neural networks
or coding-decoding processes. Much of what is understood about the
consequences of quenched randomness is based on piecemeal results rather than
exhaustive, consistent experimental and theoretical studies. This group plans
to effect such a study. They will probe this one fundamental problem, ordering
under quenched disorder, from different directions while requiring
interconnected and mutually consistent interpretations. Model systems proposed
for study include gels with random distributions of positive and negative
charges and random antiferromagnets. The gels have recently received attention
for their potential application in many different arenas.
Participating faculty and departmental affiliations: Professors C. W. Garland
(Chemistry); and A. N Berker, R. J. Birgeneau, M. Kardar, J. D. Litster, and T.
Tanaka (Physics).
The properties of polycrystalline materials are largely dominated by the
properties of their surfaces and grain boundaries. Oxides possess the greatest
range of interfacial properties of scientific and technological interest, owing
to a richness of chemical and electronic phenomena not found in most other
materials. However, due to greater complexity, these materials are at the same
time the least understood. The goal of this IRG is to develop a unified and
comprehensive understanding of the role of atomic level structure, chemistry,
and local electronic structure in determining the physical properties of
crystal interfaces. Towards this goal, a collaborative effort in the growth,
detailed characterization, and computational modeling of grain boundaries in
model oxides is proposed. The two materials chosen for study, TiO2 and ZnO,
have technological applications that depend on the behavior of their
interfaces: TiO2 is the primary opacifying component in paint and ZnO is the
material of which varistors are made. The successful growth of single grain
boundaries in these oxides and the use of electron microscopy to study their
chemistry on the nm length scale has enabled this group to approach this
problem in a way never before possible.
Participating faculty and research staff and departmental affiliations:
Professors R. W. Balluffi, Y.-M. Chiang, H. L. Tuller, J. B. Vander Sande, and
B. J. Wuensch (Materials Science and Engineering); and Dr. A. J. Garratt-Reed
(CMSE).
The discovery of high-temperature superconductivity in copper oxides has
renewed interest in the more general problem of transition metal oxides, where
strong correlations between the electrons are known to play a key role. For
example, the parent compound La2CuO4 is an antiferromagnetic insulator,
contrary to the prediction of band theory, and becomes metallic and
superconducting when doped. Many believe that the superconductivity is a new
manifestation of the correlated behavior of the electrons in the
two-dimensional copper oxide layers. It follows that the physics of strong
correlations must be better understood before the superconductivity can be
explained. The goal of this group is, therefore, to study the properties of
transition metal oxides in order to guide the development of a theory of
correlated systems and ultimately explain the mechanism of high-Tc
superconductivity. The group's strategy for reaching its goal has three parts:
detailed studies of the magnetic, electronic, and optical properties of single
crystals, development of a theoretical framework for the analysis of the data,
and a search for new compounds. The growth of large single crystals for
neutron scattering experiments is a unique strength of this effort. These
crystals made possible the discovery of low energy optical excitations in
undoped copper oxides like La2CuO4.
Participating faculty and departmental affiliations: Professors R. J.
Birgeneau, M. A. Kastner, and P. A. Lee (Physics); and H.-C. zur Loye
(Chemistry).
CMSE's programs contribute to the education of both undergraduate and graduate
students in a variety of ways. A joint program with the Materials Processing
Center (MPC) combines NSF/MRSEC support with industrial funds to bring students
from all across the nation to MIT in the summer to become involved in materials
research. The SEFs are also important in undergraduate education. Courses,
such as those in X-ray scattering and microfabrication, teach the students to
use processing and characterization facilities and to carry out research
projects using the equipment. A course entitled Materials Synthesis and
Processing, taught by the Department of Materials Science and Engineering and
initiated with partial NSF support, uses the SEFs extensively. In addition,
short courses are taught using the facilities during the Independent Activities
Period. At the graduate level, CMSE plays a critical role in the education of
almost all the students at MIT who do materials-related research. In addition
to those involved in the IRGs, the shared facilities are used by graduate
students from 11 academic departments.
CMSE collaborates with other laboratories and centers at MIT that carry out
materials-related research and engineering with direct involvement of industry
and other sectors. Collaborations are especially active with two of these, the
MPC and the Microsystems Technology Laboratories (MTL). CMSE collaborates with
these centers through joint sponsorship of research, joint publications, and
joint symposia. MPC and CMSE have a joint Industrial Advisory Board, which
reviews the effectiveness of collaboration between CMSE and industry and
recommends ways of enhancing it. The board also advises CMSE about
opportunities for modifying its research programs to address society's needs.
MPC has begun to develop aggressively industrial participation in the
appli-cation of the results of IRG research through working groups and
workshops. The cost of equipment for CMSE facilities is shared by MTL and MPC
whenever appropriate, and CMSE facilities are modified in coordination with
these organizations to assure that the overall spectrum of facilities offered
by MIT is as broad as possible without unnecessary redundancy.
The SEFs are a critical feature of CMSE's collaborations with non-MIT
personnel. The facilities are made available to any researcher from a
nonprofit institution and to industrial researchers when equivalent facilities
are not available commercially. During the past year, CMSE facilities have
been utilized by 26 commercial organizations and 11 outside academic
institutions. A research manager has been hired to assure that the SEFs meet
the needs of this wide variety of users. The current CMSE/IBM X-ray
participating research team (PRT) at the National Synchrotron Light Source
(NSLS) at Brookhaven, the CMSE/IBM/McGill PRT under construction at the Argonne
Advanced Photon Source (APS), and the Brookhaven/CMSE/AT&T/Exxon neutron
scattering PRT at the Brookhaven High Flux Beam Reactor are very special
facilities constructed and operated with direct industrial and government
laboratory collaboration. These PRTs and the neutron diffraction PRT at the
National Institute of Standards and Technology (NIST) provide time for use of
facilities to users from all sectors. Finally, several of the IRGs propose
direct research collaboration with industry and other sectors. This is
important for exchange of knowledge and the education of graduate students, for
it provides them with direct experience of industrial research.
Two permanent members were added to the staff during the past year. Neil
Rowlands joined the administrative staff as research manager in September, and
Carol Breen was appointed to the support staff in November. One male
postdoctoral associate, Laurence Lurio, was appointed on June 15, 1995.
Departures from the Center's staff over the past year include research staff
members Hans Jenssen, who retired August 31, 1994; Arlete Cassanho, who
resigned in August of 1994; Leonard Sudenfield, who resigned April 30, 1995;
and Franklin Payne, who retired June 30, 1995. In addition, one research staff
member, John Martin, passed away in August.
Of the 10 students participating in the CMSE Undergraduate Research
Opportunities Program, funded by the National Science Foundation as part of the
MRSEC Program, four were men and six were women, one of whom, Kamilah
Alexander, is African-American. Again this summer, CMSE is collaborating with
the MPC in sponsoring a joint ten-week summer internship program. Nine interns
were selected from applications submitted by 166 undergraduates from both MIT
and other universities from around the country. Four of these scholars are
women and one is an African-American man. The interns include Aristotelis
Asimakopoulos (California Institute of Technology), Behin Behrang (Yale
University), Clifford Leslie (University of Washington), Douglas Harris (MIT),
Carol Ouellette (Swarthmore College), Danielle Russell (MIT), Andrea Santoro
(Carnegie Mellon University), Jason Sebastian (University of Illinois at
Urbana), and K. Jessica Thomas (Yale University).
As part of its outreach program, CMSE participates in the cooperative
employment in its shared experimental facilities of students from Northeastern
University and Wentworth Institute. Of the six students employed this year,
one was a woman and two were African-American men. Jason Abdullah, Brian
Gregor, Elizabeth Harmon, Sleamms Petit-Maitre, Costas Pitsillides, and Andrew
Williamson worked as co-op students in three of the Center's SEFs over the
course of the past year.
CMSE also participates in the Cambridge Teenwork program that fosters after
school and summer office employ-ment of Cambridge high school students. An
Hispanic young woman, Jessenia Marquez, worked for the entire school year, and
continues to work throughout the summer.
The Center continued its very successful science and engineering summer day
camp for seventh- and eighth-grade students from a local public school who are
members of underrepresented minority groups. The students were supervised by
volunteer faculty and staff, as well as five MIT students, including one
African-American man, three African-American women, and one Hispanic woman.
These students were Arely Benavides, Sharonda Bridgeforth, Nikki Caruthers,
Dawne David, and Lakisha Powell.
In our recent NSF MRSEC proposal, we proposed to initiate the CMSE graduate
minority research assistant (RA) program to fill the need for support for
minority students in their last two years of graduate study. During the
1994-95 academic year, the Center provided RA support to an African-American
woman in the Department of Physics and an Hispanic male in the Department of
Chemistry. In addition, seed funding was granted to one female faculty member
working in the field of materials science and engineering who is a member of an
under-represented minority group.
Marc A. Kastner
MIT
Reports to the President 1994-95