Three assistant professors of electrical and computer engineering, Ehsan Afshari, Sunil Bhave and Farhan Rana, have been chosen by the Defense Advanced Research Projects Agency (DARPA) to receive DARPA 2008 Young Faculty Awards. The awards consist of grants of about $150,000 each to advance "innovative, speculative and high-risk research ideas."

Afshari works in a field he has nicknamed "optotronics," which applies the principles of optics to manipulating electrical signals in a silicon chip. He modifies the geometry of circuits to create the electrical equivalent of lenses, prisms and other optical devices on silicon. His DARPA grant will help support a project to create an electrical lens that carries out a Fourier transform at very high speed with extremely low power consumption. Fourier transform is a process that separates out the individual frequencies of a complex signal.

Bhave will develop a silicon opto-acoustic oscillator using silicon-based microresonators that will combine mechanical and optical resonance to generate a very pure, frequency-stable radio-frequency signal. Vibrations in the mechanical resonator distort the shape of the device and, therefore, its optical resonant frequency, which in turn varies the intensity of light passing through the cavity. The light is fed back repeatedly through a loop to intensify the signal at the resonant frequency.

Rana is developing nanoscale devices that operate in the terahertz frequency range (over 1,000 gigahertz). Devices operating at terahertz frequencies make possible ultrahigh-speed electronics and ultrawide band communications. Terahertz radiation penetrates living tissue without the damage associated with such ionizing radiation as X-rays and can be used for chemical and biological sensing, medical imaging and security screening. The trouble is, current electronic devices like transistors can't reach these frequencies. Rana plans to generate terahertz signals in graphene, which is a single atomic layer of carbon atoms, by creating and amplifying waves of electrons by a process similar to the way photons are created and amplified in a laser. He calls these devices "lasers for circuits."

DARPA's Microsystems Technology Office sponsors the Young Faculty Award program, designed to seek out ideas from nontenured faculty and identify the next generation of researchers working in microsystems technology. DARPA made awards this year to 39 of these "rising stars in university microsystems research."