Research Highlights

Hanan Dery Honored as a Scientific American Top 50 Technical Leader of 2007

The Board of Editors of Scientific American has cited Assistant Professor Hanan Dery as one of its top 50 technical leaders of 2007. Dery is being honored specifically as a research leader for developing the spintronics logic gate.

Known as the "Scientific American 50," the award is in its sixth year and honors 50 individuals, teams, companies, business, or policymakers who have demonstrated outstanding technological leadership. Winners during the past several years have included Larry Page and Sergey Brin, founders of Google (sharing the distinction of 2005 Business Leader of the Year), research philanthropist Fred Kavli (2005 Policy Leader of the Year), renowned stem cell researcher Douglas A. Melton, Professor of the National Sciences at Harvard (2004 Policy Leader of the Year), and Nobel prize-winning neurobiologist Roderick MacKinnon, Professor of Molecular Neurobiology and Biophysics of Rockefeller University (2003 Research Leader of the Year). The complete list of winners for the Scientific American 50 appears in the January 2008 issue of Scientific American.

Dr. Dery joined the Department in July, 2007. Previously, he was a Postdoctoral Associate in Lu Sham's group in the Department of Physics, University of California San Diego (UCSD). During this time, he worked on spintronics, seeking ways to integrate information based on electron spin into semiconductors. Dery earned his Ph.D. in Electrical Engineering from Technion-Israel Institute of Technology in 2004. His Ph.D. research was in optoelectronic nanostructure devices with a focus on nonlinear gain processes and carrier dynamic properties. In the Fall 2007 semester, Dery taught graduate course ECE-492, Special topic in spin-based electronics: Theory, Devices & Applications; and in Spring 2008, he will teach ECE-200, Computer Architecture.

More on Spintronics

A semiconductor computer circuit based on the spin of electrons? For those of us who came of age back when electronics were based on electric current producing binary ones and zeroes, the notion of using electron spin for semiconductors is beyond visionary. Yet this is a field of emerging strength in electronics research.

This type of device is expected to be highly scalable and have much greater computational capacity than silicon circuits in use today. Basically, a spintronic device encodes information using the charge of the electrons, as well as their magnetic, or spin, states. A key to successful spintronics is to overcome the weakness of the magnetic signal, something that Dery and his associates have been able to do.

Dery's spintronic circuit (Nature, June 2006) is composed of logic gates, each of which consists of a semiconductor layer topped by five magnetic contacts (see below). The magnetic state of each contact is determined by electron spin, between four of the magnetic contacts and the semiconductor, and then the fifth magnetic contact reads the result. Working with Dery were his collaborators at UCSD: Lu J. Sham, P. Dalal, and L. Cywinski.

"Spin-based electronic devices allow the construction of reprogrammable circuits without hindering performance," says Assistant Professor Dery. In addition, the integration of spintronics into a semiconductor reduces the size of circuits and speeds up computations.

Striemer & Fauchet  Super-thin Filter, 50 Atoms Thick, Sorts Individual Molecules 2/07

"Professors Feldman, Margala, Ampadu and Shapir Receive $1.1M NSF Funding for Nanoelectronics" Professors Marc Feldman, Martin Margala and Paul Ampadu of the Department of Electrical and Computer Engineering, and Professor Yonathan Shapir of the Department of Physics and Astronomy, are the recipients of a National Science Foundation Nanoscale Interdisciplinary Research Team (NIRT) grant, to study "Utilization of Ballistic Deflection Phenomena for Room Temperature Devices and Circuitry".

The four year grant will explore using nonlinear ballistic electron transport in mesoscopic structures at room temperature to construct a new generation of electronic devices and circuitry. While ballistic transport is usually associated with the quantum regime at cryogenic temperatures, certain effects such as "ballistic deflection" have been found to be quite robust even at room temperature, in nanoscale structures. The grant will fund the design, fabrication and testing of ballistic devices and circuits, as well as theoretical investigations of the underlying physics behind their operation. Preliminary results on the concept, initially developed by Quentin Diduck, Prof. Margala's PhD student, suggest that such ballistic devices can provide low power, room temperature, sub-100 nm size, Terahertz transistors and other devices, that will be suitable for a multitude of practical applications. (Full news release is here) 8/06

New Chip Design Delivers Better Performance, Longer Battery Life for Cell Phones, WiFi, and Other Wireless Communications 4/06

Breakthrough Chip Delivers Better Digital Pictures for Less Power. 12/05 (PDF version)

Electrical and thermal modulation of silicon photonic bandgap microcavities containing liquid crystals. 2/05 (PDF)

Optical gain in different silicon nanocrystal systems. 10/04 (PDF)

Bocko, Williams, and Fairchild: Innovators honored 2/04

Two Scientists Named Best Inventors of 2003 by 'R&D Magazine' 11/03

Reversible Data Hiding Embeds Data in Pictures Without Distortion 9/02