Step forward for computing by light

From BBC news:

Engineers and physicists have discovered a property of silicon which could aid the development of faster computers.

Currently, copper wires transfer information in a computer; the process is slowed down as the wires heat up.

“Photonic” and “spintronic” computing is the principle of transferring information by light or electron spin.

This new property means that silicon-based light detectors identify spin, so more information can be transferred.

Spin is a property of sub-atomic particles, which influences the ordering of electrons and nuclei in atoms and molecules.

The discovered property is usually observed in materials containing heavy elements, which are difficult to integrate into existing computing systems that are composed mainly of silicon.

Silicon is a highly symmetrical crystal, but by changing the geometry of it, the team was able to impart “chiral” properties to it. Something is chiral if the mirror image of the object cannot be superimposed on the original.
This chirality means that silicon-based detectors are able to detect the spin of electrons and light, and as a result allow more information to be transmitted.

“The whole computer running with light is a distant dream, but some copper interconnectors can be replaced with light and photo-detector devices,” Professor Ritesh Agarwal, who led this study at the University of Pennsylvania, told BBC News.

“This is only around five years away from now. The technology already exists, but this can bring added functionality.”

The discovery was made by accident, while investigating heavier materials.

As well as discovering chirality in silicon, this study has wider implications for materials science.

“It’s the same silicon, all we’ve done is cut it in a particular direction,” explained Professor Ritesh Agarwal.

This is a step towards engineering new, useful properties by changing the geometry of a material.

Hee-Suk Chung completes his post-doctoral candidature

Hee-Suk Chung has completed his post-doctoral candidature with the group. He is headed to Samsung, South Korea. The group wishes him all the very best for his future and will surely miss him and his expertise!

Ritesh Agarwal Receives 2010 NIH New Innovator Award

Excerpted from the UPenn SEAS website:

Ritesh Agarwal, assistant professor in the department of Materials Science and Engineering, has been awarded the 2010 NIH Director’s New Innovator Award from the National Institutes of Health, providing $1.5 million over five years to support his research into improving biological imaging using nanotechnology.

The awards are given by the NIH to address two important goals: stimulate highly innovative research that has the potential for significant impact, and support promising early stage investigators who propose bold new approaches that have the potential to produce a major impact on a broad area of biomedical or behavioral research.

“It is a great honor and a wonderful opportunity for us to assemble novel nanoscale optoelectronic probes to study intracellular activity with unprecedented resolution,” states Agarwal. “A unique aspect of this award is that it does not require any preliminary data and thus allows people like me with limited experience in biology or medicine to expand our expertise and to attack very challenging problems. This award will have a transformational effect on my research program at Penn.”

Agarwal’s project, “Optoelectronic Nanowire Probes for Investigation of Intracellular Processes,” will seek to assemble nanowire devices with optical and electrical functions to probe cell and intracellular dynamics with unprecedented resolution. By combining nanowire waveguides, fluorophores, quantum dots, lasers, light emitting diodes, and photodetectors, they hope to create a new generation of biological imaging: probes that can target subcellular regions, measuring for the first time, in real time, chemical reactions, cellular signalling and cellular reactions due to complex phenomena like a locally delivered drug.

The ability to visualize in vitro intra- and inter- cellular processes in real time will aid the design of new drugs for a large number of diseases that impact public health.