A research team led by Professors Christine Ortiz, Krystyn Van Vliet,
and Paula Hammond of IRG-II have designed and characterized an
electrochemically responsive polymer nanocomposite thin film with
control over film thickness and mechanical properties. Specifically,
they have used layer-by-layer assembly to create a thin film containing
cationic linear poly(ethyleneimine) (LPEI) and anionic Prussian Blue
(PB) nanoparticles.
Research funded in part by the MIT MRSEC has
led to a discovery of one-way photonic behavior. A team made up of MIT
physicists Zheng Wang, research scientist in MIT's Research Laboratory
of Electronics; recent MIT PhD recipient Yidong Chong; Professor John
Joannopoulos; and Professor Marin Soljacic have developed and
experimentally tested photonic crystals that restrict light to travel
in only one direction without back-scattering, even in the presence of
large disorders.
Polyurethanes have many properties that qualify them as high
performance polymeric materials, but they still suffer from mechanical
damage. We report the development of polyurethane networks that exhibit
self-repairing characteristics upon exposure to ultraviolet light. The
network consists of an oxetane-substituted chitosan precursor
incorporated into a two-component polyurethane. Upon mechanical damage
of the network, four-member oxetane rings open to create two reactive
ends.
The “life” in organisms is due to the specific molecular interactions of proteins, called molecular recognition, that leads to a self-assembly and a large diversity of functions in biology;
Emulating biology, in Molecular Biomimetics, GEMSEC is developing novel protocols towards materials and systems based on proteins, engineered in our labs;
GEPI, Genetically engineered peptides for inorganics, are as building blocks; synthesizers, erectors, and assemblers, in forming functional molecular materials for implemen
A team of researchers, led by Yoel Fink of the MIT MRSEC, has developed light-detecting fibers that can be woven together to create a flexible, basic camera. These fibers are each less than a millimeter in diameter, and consist of several nested layers of light-detection materials. The fibers measure the intensity of the light illuminating them and convert it to an electrical signal, which is then fed into a computer that creates an algorithm to assimilate the data and create a black-and-white image on a screen.
Graphene is comprised of a single layer of C atoms in a hexagonal lattice array. The electronic state of graphene is of great interest because the electron energy increases linearly with momentum, just like for photons and neutrinos. This is called a massless, Dirac dispersion. The nature of the electronic state at zero energy (the “Dirac point”) in a strong magnetic field H is currently the subject of theoretical debate.
In an ordinary insulator, such as diamond, the occupied electronic states are separated from unoccupied states by a large energy “gap”. The gap prevents current flow when an electric field is applied. Recent research has uncovered a new class of insulators, called topological insulators, in which electrons can bypass the energy gap by moving in surface states. The energy vs. momentum dispersion of these unusual surface states are Dirac-like. They exhibit unusual topological properties which may be important for quantum computing. Previously, a group at Princeton led by Hasan and Cava detected these unusual surface states in the bismuth alloy Bi1-xSbx using angle-resolved photoemission spectroscopy (ARPES). In a new breakthrough, Hasan and Cava have now identified a second Topological Insulator, Bi2Se3. Compared with Bi1-xSbx, the surface states of Bi2Se3 are far easier to investigate. Bi2Se3 has only 1 Dirac state on the surface, which greatly simplifies the analysis of its measured properties. Its dispersion, shown as the red curves SS in the figure (right panel), displays clearly the distinctive champagne-glass profile of Dirac electrons. In addition, the energy gap is much larger, which allows the topological states to be studied even at room temperature. The new material should greatly facilitate research on this new class of materials.
Left: The photoemission intensity at the Fermi level reveals a single circular feature formed by the topological surface state. Right: The underlying surface band dispersion of Bi2Se3 reveals a Dirac cone as well as a single Fermi level crossing confirming that it is a strong topological insulator
A group led by Gerbrand Ceder and Angela Belcher of the MIT MRSEC have made a significant advancement in battery research: for the first time, this team has used genetically engineered viruses to build both the positively and negatively charged ends of a lithium-ion battery.
A research team led by Professors Christine Ortiz, Krystyn Van Vliet,
and Paula Hammond of IRG-II have designed and characterized an
electrochemically responsive polymer nanocomposite thin film with
control over film thickness and mechanical properties. Specifically,
they have used layer-by-layer assembly to create a thin film containing
cationic linear poly(ethyleneimine) (LPEI) and anionic Prussian Blue
(PB) nanoparticles.
Polyurethanes have many properties that qualify them as high
performance polymeric materials, but they still suffer from mechanical
damage. We report the development of polyurethane networks that exhibit
self-repairing characteristics upon exposure to ultraviolet light. The
network consists of an oxetane-substituted chitosan precursor
incorporated into a two-component polyurethane. Upon mechanical damage
of the network, four-member oxetane rings open to create two reactive
ends.
A team of researchers, led by Yoel Fink of the MIT MRSEC, has developed light-detecting fibers that can be woven together to create a flexible, basic camera. These fibers are each less than a millimeter in diameter, and consist of several nested layers of light-detection materials. The fibers measure the intensity of the light illuminating them and convert it to an electrical signal, which is then fed into a computer that creates an algorithm to assimilate the data and create a black-and-white image on a screen. 
A group led by Gerbrand Ceder and Angela Belcher of the MIT MRSEC have made a significant advancement in battery research: for the first time, this team has used genetically engineered viruses to build both the positively and negatively charged ends of a lithium-ion battery.