Rensselaer Catalog 2008-2009 [Archived Catalog]
Center for Terahertz Research
Director: Xi-Cheng Zhang
Center Home Page: www.rpi.edu/terahertz
The faculty members of the Center for Terahertz Research are the most active scientists in exploiting the unique advantages of terahertz (THz) radiation. Using the relatively unexplored terahertz portion of the electromagnetic spectrum, they are creating innovative sensing and imaging technologies that hold enormous potential in non-destructive testing, genetics diagnostics, microelectronics, and the chemical and biological materials identification fields that support homeland defense initiatives.
Spaced along the electromagnetic spectrum are microwaves, infrared, visible light, and X-rays. Between microwaves and infrared, at a frequency of more than a trillion cycles per second, lies terahertz radiation. In the same way that visible light can create a photograph, radio waves can transmit sound, and X-rays can see shapes within the human body, T-rays can create images or carry information.
The promise of terahertz wave radiation, known as “T-rays”, is being realized through ongoing research projects at the THz Center’s state-of-the-art laboratories: The W. M. Keck Laboratory for THz Science, Dr. Michael Shur’s THz Electronics laboratory, Dr. Masashi Yamaguchi’s THz Optoelectronics laboratory, Dr. Ingrid Wilke’s THz Spectroscopic laboratory, Dr. Gwo-Ching Wang’s NSF-IGERT THz-GHz laboratory, and Dr. Xi-Cheng Zhang’s THz Photonics laboratory. Together, these researchers are overcoming significant challenges posed by the fundamental physics that underlie this large—and historically inaccessible—portion of the electromagnetic spectrum.
Rensselaer’s THz research team has become the established leader in the development and application of terahertz technology. Their breakthroughs in microscopy, imaging, and development of THz emitters and detectors have opened the door to tremendous opportunities for THz radiation throughout major industries. For example, Dr. Shur’s group reported the use of novel electronic devices to generate and detect CW THz wave at room temperature; Dr. Wilke reported the use of InN as a new THz material for intense THz wave emission; Dr. Yamaguchi is developing tunable GHz-THz acoustic spectroscopy for non contact direct acoustic transport measurement and Impulsive Stimulated Thermal Scattering (ISTS) for non contact thermal transport measurement in nanomaterials; and Dr. Zhang’s and Dr. Yamaguchi’s groups have demonstrated the generation, manipulation, amplification, and detection of THz waves in ambient air with amplified laser beams.
The THz Center has also designed and built portable THz wave imaging systems, which were tested and approved by NASA for the nondestructive testing of foam insulation used on space shuttles. One compact THz imaging system was installed in NASA’s George Marshall Space Flight Center and another at Lockheed Martin. In the Center’s Compact THz Applications lab, Mr. Brian Schulkin, NSF-IGERT Fellow and IMRA Fellow (and winner of the inaugural 2007 Lemelson-Rensselaer Student Prize, one of the 2007 Scientific American 50) has designed and fabricated a portable handheld THz spectrometer for defense applications.
Research at the center is currently focused on the generation and detection of free-space THz beams using ultra-fast optics and electro-optic crystals. A primary goal is to develop and refine the instrumentation—finding higher dynamic ranges, achieving faster data acquisition, and increasing sensitivities to enable the detection of monomolecular layers—that will move THz technology beyond its current niche applications to support wider use in nondestructive analysis, homeland security and biomedicine. During the last several years, scientists and engineers from more than 100 universities, companies, and clinics have visited, and Rensselaer’s THz team has helped scientists from 21 countries learn to use THz sensors.
Rensselaer’s terahertz research group has received more than $18 million in grants from the National Science Foundation, Army Research Office, Army Research Laboratory, Air Force Office of Scientific Research, Department of Energy, Defense Advanced Research Projects Agency, Department of Homeland Security, Navy, NASA, and the W.M. Keck Foundation. Currently, seven companies support the THz Center.
The center’s labs are equipped with the most advanced photonic and opto-electronic instrumentation for generating, measuring and recording picosecond and femtosecond terahertz radiation waves. Rensselaer’s Center for Terahertz Research stands at the forefront of terahertz technology, a science still in its infancy yet expected to become one of the most promising research areas for transformational imaging in the 21st century.
Yunqing Chen, Research Assistant Professor of Physics.
Jianming Dai, Research Assistant Professor of Physics
Albert Redo-Sanchez, Research Assistant Professor of Physics.
Michael Shur, Patricia W. and C. Sheldon Roberts Professor, Professor of ECSE & Physics.
Gwo-Ching Wang, Professor of Physics and Head of Physics Department.
Ingrid Wilke, Assistant Professor of Physics.
Masashi Yamaguchi, Assistant Professor of Physics.
X.-C. Zhang, J. Erik Jonsson Distinguished Professor of Science, Professor of Physics and ECSE.