Yujie Ding receives coveted optics honor

	Yujie Ding (right), professor of electrical and computer engineering, studies terahertz radiation in his lab with visiting research scientist Yi Jiang.

Yujie Ding, professor of electrical and computer engineering, has been elected a Fellow of the Optical Society of America, the most prestigious honor bestowed on researchers in the fields of optics and photonics.
Ding was cited by OSA for “key contributions to the efficient generation of widely-tunable, high-power, monochromatic terahertz pulses and terahertz frequency upconversion using parametric frequency mixing.”
Ding, who joined the faculty in 2002, has gained world-renown in the past 10 years for his research into terahertz radiation, or waves.
A terahertz (THz) is a unit of electromagnetic-wave frequency equivalent to one trillion hertz, with one hertz equaling one cycle per second.
Terahertz (THz) frequencies, ranging from 0.1 to 10 THz, are one of the commonest but least-utilized forms of radiation. Unlike x-rays, THz radiation is non-ionizing and thus not harmful to tissue, making THz frequencies suitable for noninvasive medical imaging. THz radiation can penetrate clothing and plastics, making the frequencies potentially useful in surveillance and in remote detection of concealed weapons. THz radiation can also detect the unique spectral “fingerprints” of some drugs and explosives.
The development of THz devices, however, has been limited by challenges in generating and detecting THz radiation.
Ding has achieved several key successes in overcoming these challenges.
In an article published last summer in Applied Physics Letters, Ding reported that he and his visiting research scientist had generated coherent THz pulses by combining the frequencies of two carbon-dioxide laser beams in gallium-selenide (GaSe), a nonlinear crystal.
“This is the first report of high-power THz generation based on frequency-mixing two CO2 lasers in a bulk nonlinear crystal,” Ding told the online journal optics.org.
“Usually when people generate THz radiation, they get a broad bandwidth,” Ding said. “We have been able to generate a very narrow bandwidth with greater spectral density and greater potential for chemical sensing.”
Ding and his colleagues published a second recent paper, this one titled “Fingerprinting Insulins in the Spectral Region from Mid-Infrared to THz,” in the International Journal of High Speed Electronics and Systems.
Ding has published more than 420 technical articles and has served as subcommittee member and session chair at a dozen international meetings in his field, including CLEO and LEOS, the two most important conferences of optics and photonics researchers.
The OSA, which was founded in 1916, has more than 15,000 members, including scientists, engineers, teachers, technicians and business leaders, representing 100 countries.
--Kurt Pfitzer