It might not be science fiction much longer.
Researchers at Sandia National Laboratories are developing the next generation of screening devices that will identify hazardous and toxic materials even if concealed by clothing and packaging materials.
Working in the underutilized terahertz (THz) portion of the electromagnetic spectrum that lies between microwaves and infrared, a team of Labs scientists is harnessing Sandia's strengths in a variety of technical areas with the goal of building a highly integrated miniaturized terahertz transmitter-receiver (transceiver) that could make a number of applications possible.
The project, the Terahertz Microelectronics Transceiver Grand Challenge, is in its second of three years of funding through Sandia's internal Laboratory Directed Research and Development program.
Sandia is a National Nuclear Security Administration (NNSA) laboratory.
"The technology being developed in the Grand Challenge can be used to scan for items such as concealed weapons or materials, explosives, and weapons of mass destruction," says Mike Wanke, principal investigator. "In addition, we believe it will find applications in advanced communication systems and high-resolution radars. However, the infrastructure needed to move the terahertz technology from the laboratory to the field is unavailable right now. We want to develop that infrastructure and invent the necessary technologies."
Wanke says over the past three years, "the terahertz situation has begun to change dramatically, primarily due to the revolutionary development of terahertz quantum cascade lasers."
These tiny lasers are semiconductor sources of terahertz radiation capable of output powers in excess of 100 mW. Previously, such powers could only be obtained by molecular gas lasers occupying cubic meters and weighing more than 100 kg, or free electron lasers weighing tons and occupying entire buildings.
Quantum cascade laser-based systems can be less than the size of a baseball and powered from a nine-volt battery. Sandia has been a leader in developing this new technology and in collaboration with MIT is responsible for several world performance records for the lasers. Also, the Labs and its partners are the only US institutions that have demonstrated the ability to grow the unique semiconductor crystals such that they can be turned into operating terahertz quantum cascade lasers. The crystals are grown by Sandia research scientist John Reno, an expert in molecular beam epitaxy, a method of laying down layers of materials with atomic thicknesses onto substrates.
Sandia researchers spent the first year of the Grand Challenge using Sandia's unique strengths in integrated microelectronics and device physics to develop components that are now being combined to create an integrated THz microelectronic transceiver, a core enabling element.
The team is currently developing the receiver, doing systems tests and exploring packaging requirements. At the end of three years, the researchers expect to have an actual working prototype capable of detecting the materials and chemicals by reading distinctive molecular spectral "signatures."
"Most materials and chemicals have their own unique terahertz spectral signatures," Wanke says. "A terahertz transceiver system would be able to measure, for example, the signature of a gas and determine what it is."
"Atmospheric scientists and radio astronomers have spent years developing terahertz spectral signature databases to identify chemicals in nebula and planetary atmospheres," says Greg Hebner, program manager. "Even though the current devices are washing machine-sized, they are located in a few observatories, and one is even flying on a satellite. To address specific national security problems, we are working on reducing the size, weight, and power requirement as well as expanding the existing spectral databases."
In addition to monitoring for concealed hazardous materials, Mike believes a terahertz system can be used to monitor the air for toxic materials. Using air sampling technology developed at Sandia and other locations, hazardous vapors can be preconcentrated. Shining light from the quantum cascade laser through the concentrated sample provides a direct identification of the vapor. This technology can be used in conjunction with existing mass spectrometer-based systems to reduce false identifications.
"We are very optimistic about working in the terahertz electromagnetic spectrum," Wanke says. "This is an unexplored area and a lot of science can come out of it. We are just beginning to scratch the surface of what THz can do to improve national security."
Chris Burroughs | EurekAlert!
Breakthrough with a chain of gold atoms
17.02.2017 | Universität Konstanz
New functional principle to generate the „third harmonic“
16.02.2017 | Laser Zentrum Hannover e.V.
In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport
Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...
The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.
The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...
Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...
Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".
Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...
13.02.2017 | Event News
10.02.2017 | Event News
09.02.2017 | Event News
17.02.2017 | Medical Engineering
17.02.2017 | Medical Engineering
17.02.2017 | Health and Medicine