DARPA’s THz Electronics ProgramJul 31, 2012 13:11 UTC by Defense Industry Daily staff
In 2009, the US Defense Advanced Research Projects Agency (DARPA) began awarding contracts for innovative research proposals under its Terahertz (THz) Electronics Program. Readers will probably be asking the same question that crossed our minds, namely, “when can I expect this, instead of my 2 GHz laptop?”
If Moore’s Law continues, the answer is somewhere between 2025 – 2030. The military thinks “why wait?”, and DARPA has a long history of helping to fund computing breakthroughs – from that minor nuisance we call the Internet to modern work on Gallium Nitride (GaN) semiconductors, non-thermionic transistors, research into graphene circuits, and more. Now, their Terahertz (THz) Electronics program is looking for technologies to enable revolutionary advances in electronic devices and integrated circuits, allowing them to reach THz frequencies (at least a trillion cycles per second).
THz Electronics: Goals & Barriers
Commenting on the THz Electronics program, Dr. Mark Rosker, program manager of DARPA’s Microsystems Technology Office, said:
“The THz Electronics Program will develop a technology for integrated circuits operating at far higher frequencies than ever possible before. This will be crucially important for emerging applications like terahertz communications and radars. But of potentially even greater consequence, this program will drive the state of the art in high performance III-V electronics, with vast implication to RF circuits and systems operating at more conventional (microwave and millimeter-wave) frequencies.”
So what’s the issue? As DARPA’s own program brief explains:
“Until recently, active electronics using solid-state technologies were unable to access sub-MMW (millimeter wave) frequencies directly due to insufficient transistor performance. The compromise electronic option was to use frequency conversion to multiply circuit operating frequencies up from millimeter wave frequencies. Such an approach limited the output power level of the devices and the achievable signal-to-noise ratio. It also restricted the devices to relatively large sizes in terms of footprint and weight. These limitations and restrictions prevented widespread implementation and the subsequent exploitation of the sub-MMW frequency band. The enabling technology necessary to exploit the sub-MMW band is monolithic microwave integrated circuits (MMICs) that will operate up to THz frequencies. These THz MMICs or TMICs, require THz transistors with maximum oscillation frequencies (fmax) well above 1 THz.”
The program will work to develop a path to technologies such as THz transistor devices and integrated circuits, and THz high power amplifier modules for military application. The critical bridges to that future include micromachined vacuum electronics Terahertz High Power Amplifier Modules, and Terahertz Transistor Electronics (multi-THz InP HBT and InP HEMT transistor technologies, and THz low-loss inter-element interconnect and integration technologies).
Contracts and Key Events
All contracts are managed by the US Defense Advanced Research Projects Agency. Note that “metrology” is the science of measurement.
Under Phase 1, they developed a Monolithic Integrated Circuit that operated at 670 GHz. The company also developed and tested low-noise amplifiers and power amplifiers.
July 10/12: From the Lawrence Berkeley National Laboratory, some good news for the field:
“A multi-institutional team of researchers that included scientists with the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) has created the first artificial molecules whose chirality can be rapidly switched from a right-handed to a left-handed orientation with a beam of light. This holds potentially important possibilities for the application of terahertz technologies across a wide range of fields… Chirality is the distinct left/right orientation or “handedness” of some types of molecules, meaning the molecule can take one of two mirror image forms. The right-handed and left-handed forms of such molecules, called “enantiomers,” can exhibit strikingly different properties.
…Working with terahertz (THz) metamaterials engineered from nanometer-sized gold strips with air as the dielectric – Zhang and his colleagues fashioned a delicate artificial chiral molecule which they then incorporated with a photoactive silicon medium. Through photoexcitation of their metamolecules with an external beam of light, the researchers observed handedness flipping in the form of circularly polarized emitted THz light. Furthermore, the photoexcitation enabled this chirality flipping and the circular polarization of THz light to be dynamically controlled.”
April 20/11: Northrop Grumman Space & Mission Systems in Redondo Beach, CA receives a $12.5 million cost-plus-fixed-fee contract modification for the Terahertz (THz) Electronics Program. This contract focuses on critical device and integration technologies for this phase’s high end of 1.03 THz compact, high-performance electronic circuits.
Work will be performed in Redondo Beach, CA (82.58%); Charlottesville, VA (1.84%); Pasadena, CA (9.38%); Charlottesville, VA (3.51%); Tempe, AZ (1.73%); and University Park, PA (0.96%). Work is expected to be complete April 16/14 (HR0011-09-C-0062). See also April 3/09 entry.
May 6/09: Teledyne Scientific & Imaging in Thousand Oaks, CA received an $18.8 million cost-plus-fixed-fee contract to develop transceiver arrays; specifically, receivers and exciters at carrier frequencies of 670 GHz, 850 GHz, and 1030 GHz (HR0011-09-C-0060).
April 3/09: Northrop Grumman Aerospace Systems (formerly, Space and Mission Systems) in Los Angeles, CA received a $37 million contract for development of military and space satellites’ active receivers and transmitters operating at 670 gigahertz that ensure transmission of high-resolution images and other applications (HR0011-09-C-0062).
April 3/09: DARPA awards Northrop Grumman Electronic Systems an $8.9 million contract to develop and demonstrate technologies for high power amplification (HPA) of THz signals in compact HPA modules. These include demonstration of a power amplifier device capable of amplifying radiation at THz frequencies, the development of a compact THz HPA module (including an antenna and the ability to integrate with a solid-state exciter circuit), and THz metrology (HR0011-09-C-0061).
April 1/09: DARPA awards SAIC an $11.6 million contract to develop and demonstrate technologies for high power amplification (HPA) of THz signals in compact HPA modules. These include demonstration of a power amplifier device capable of amplifying radiation at THz frequencies, the development of a compact THz HPA module (including an antenna and the ability to integrate with a solid-state exciter circuit), and THz metrology (HR0011-09-C-0063).
- DARPA – THz Electronics
- Lawrence Berkeley National Laboratory (July 10/12) – Metamolecules That Switch Handedness at Light-Speed