Nanophysics
Research in nanophysics and novel materials are emphasized. Faculty are involved in several research fields at the frontiers of these areas: spintronics, nanomagnetism, superconductors, semiconductors, ferromagnets, mesoscopic physics, left-handed metamaterials, quantum chaos, nanotechnology and nanoparticle synthesis.
- Spintronics
Future
electronic devices are predicted to take advantage
of the "spin" property of electrons. This
could lead to devices for information technology with
new functionality and could be crucial for quantum
computers. Research at Northeastern seeks new materials
and structures for spin-valve and spin-transistor
applications..- Nanomaterials and Nanomedicine
Nanomedicine is an interdisciplinary paradigm that seeks to exploit recent developments in nanotechnology towards the key medical problems of early diagnosis and targeted therapy. Ongoing projects include functionalized nanoparticles, energy, drug and gene delivery using nanoparticles, electromagnetic hyperthermia, and magnetic nanoparticles as MRI contrast agents.- Nanomagnetism
Magnetism
on the nanometer scale is a crucial ingredient for
tomorrow's data storage devices. Research is aimed
at the design and synthesis of semiconductors which
are also magnetic. An MBE (molecular beam epitaxy)
facility is configured for growing quantum wells and
quantum dots of magnetic semiconductors.
Materials
with negative refractive index, also referred to as
Left-Handed Metamaterials, display entirely new aspects
of propagation of microwave and optical electromagnetic
waves. The Northeastern group has fabricated these
"meta-materials" and has demonstrated some
of their unusual microwave properties. We are also
carrying out theoretical analytical and numerical
simulations to develop new metamaterials and devices.
Northeastern's
NSOM (near-field scanning optical microscope) photoluminescence
and fluorescence spectroscopic facility and STM/BEEL
(scanning tunneling microscope/ballistic electron
emission luminescence) facility are used to optically
probe semiconductor nanostructures and multifunctional
gold nanoparticles. Research programs are focused
on InGaAs, InAs, and InP quantum dots, magnetic polarons
in magnetic semiconductors, and nanoparticle intercellular
tracking studies. Work also includes high-speed optical
switching in magnetic quantum well structures.
Electrons
confined to a 2-dimensional quantum well behave anomalously.
Ongoing experiments at ultra-low temperatures are
beginning to unravel the true nature of the collective
interaction of confined electrons and its relation
to the metal-insulator transition.
Electrons
confined to a 2-dimensional quantum well behave anomalously.
Ongoing experiments at ultra-low temperatures are
beginning to unravel the true nature of the collective
interaction of confined electrons and its relation
to the metal-insulator transition.The Nanophysics faculty include Professors Don Heiman, Nathan Israeloff, Sergei Kravchenko, Latika Menon, Clive Perry, and Srinivas Sridhar.
Theoretical Condensed Matter Physics
The theoretical condensed matter physics group enjoys a great diversity of research programs that span forefront areas of hard/soft condensed matter physics as well as emerging areas at the intersection of physics and other disciplines. The group hosts several postdocs and visiting scientists and benefits from access to several on-campus state-of-the-art computational facilities. Highlights of current research activities of selected group members include:
- Electronic Structure and Spectroscopy of Novel Materials
Professor Arun Bansil's is the director of the Advanced Scientific Computation Center and of the ELMO Laboratory for science teaching. His research focuses on questions concerning the electronic structure and spectroscopy of high-temperature superconductors and other novel materials, including nano-particle systems. His group is developing and implementing theoretical methodologies for carrying out first-principles calculations of spectral intensities relevant for angle-resolved photoemission, resonant inelastic x-ray scattering, scanning tunneling microscopy, positron-annihilation angular correlation, and other highly resolved spectroscopies, including effects of strong electron correlations. These investigations are aimed at elucidating the nature of electronic states at and near the Fermi energy, the mechanism of superconductivity in high temperature superconductors, and a variety of other interesting questions, and involve extensive collaborations inside and outside the US.
- Network Science
- Professor László Barabási heads the new Center for Network Science. His group's research is aimed at elucidating the organizing principles that govern the complex emergence and behavior of a wide range of technological, biological, and social networks. His research on biological networks is aimed at understanding the complex interactions of elementary units in between the cell's numerous constituents including proteins, DNA, RNA, and small molecules. This research exploits protein-chip and microarray gene expression data to study various metabolic, signaling and transcription-regulatory networks that emerge from these interactions and that are key for understanding the cell's functional organization and human diseases.
- Theoretical/Computational Materials Science and Cardiac Nonlinear Dynamics
Professor Alain Karma heads the Center for Interdisciplinary Research on Complex Systems. His group's research is broadly aimed at understanding the behavior of complex nonlinear systems, in particular the emergence and evolution of patterns in these systems. Research in materials science focuses on the development of phase-field methodologies rooted in nonequilibrium statistical physics to simulate the dynamics of phase boundaries and other interfaces in problems ranging from microstructural pattern formation in alloys to crack propagation and crystal decohesion. In cardiac nonlinear dynamics, his group's research focuses on elucidating complex cellular and tissue-scale processes that cause life-threatening heart rhythm disorders and on developing new therapeutic approaches to suppress these disorders.
Professor Jeff Sokoloff's research focuses on elucidating complex atomic-scale mechanisms of wearless friction between solid surfaces using a variety of analytical and computational methods. Topics under current investigation include studies of a proposed mechanism for the reduction of friction by a lubricant, understanding why thin films are able to slide under the exceedingly weak inertial forces exerted on the films during quartz crystal oscillations in microbalance experiments designed for studying friction, and the fundamental study of lubrication mechanism due to polymer brush coatings.
The primary goal of Professor Armen Stepanyants' group is to understand the principles governing synaptic connectivity in the mammalian brain. Among several fundamental questions studied are: how do neurons find appropriate synaptic targets in the course of development, and how do neuron circuits change during learning and memory? What is the connectivity diagram in the adult cortical column? Is there an optimization principle which accounts for the design and the evolution of the cortex?The Theoretical Condensed Matter group includes Professors Arun Bansil, László Barabási, Jorge José (Emeritus), Alain Karma, Jeffrey Sokoloff, Armen Stepanyants, Alan Widom, and Fa-Yueh, Wu (Emeritus).