Realizing good electrical contacts is critical to harnessing the full potential of emerging two-dimensional materials including graphene and various transition metal dichalcogenides for electronics, optoelectronics, and spintronics applications. The study examines the nature of such contacts and illuminates pathways to optimizing the injection of both charge and spin into atomically-thin semiconductors.
Members from ECE’s Nanoelectronics Research Lab, in collaboration with researchers at the Swiss Federal Institute of Technology-Lausanne (EPFL), have recently published a comprehensive study on the nature of charge and spin injection into atomically-thin two-dimensional (2D) semiconductors in the prestigious journal Nature Materials.
2D materials belonging to the graphene family, various transition metal dichalcogenides including molybdenum disulphide (MoS2) and tungsten diselenide (WSe2), as well as other 2D semiconductors such as monolayer Black Phosphorus have displayed unique potential in overcoming the limitations of conventional bulk materials (such as silicon and III-V semiconductors) for a number of exciting applications in electronics and optoelectronics, as well as spintronics and valleytronics. However, ensuring low-resistance or optimal contacts to such materials is the primary hindrance to using this technology.
Professor Banerjee’s group have made seminal contributions toward advancing the understanding of contacts to 2D materials and have also spearheaded the use of these materials for overcoming power dissipation and other fundamental challenges in nanoscale transistors, interconnects and sensors.
With an impact factor of 36.5, Nature Materials is the #1 ranked research journal in materials science covering all areas of materials including their nanoscale, biological and energy aspects.
Gossard, a research professor and professor emeritus of materials and of electrical and computer engineering at UC Santa Barbara, is among eight recipients named to receive the National Medal of Technology and Innovation and nine recipients of the National Medal of Science. All will be feted at a White House ceremony early next year.
Announced at the White House on December 22nd, President Obama said, “Science and technology are fundamental to solving some of our nation’s biggest challenges. The knowledge produced by these Americans today will carry our country’s legacy of innovation forward and continue to help countless others around the world. Their work is a testament to American ingenuity.”
The National Medal of Technology and Innovation was created by statute in 1980 and is administered for the White House by the U.S. Department of Commerce’s Patent and Trademark Office. The award recognizes those who have made lasting contributions to America’s competitiveness and quality of life and helped strengthen the nation’s technological workforce. A distinguished independent committee representing the private and public sectors submits recommendations to the president.
“I am thrilled and honored to join with our colleagues in congratulating Professor Gossard on his selection for the prestigious National Medal of Technology and Innovation,” said UC Santa Barbara Chancellor Henry T. Yang. “His creative approach to solving problems, combined with his wide-ranging expertise, relentless curiosity and lifelong passion for frontier-expanding research, has led to remarkable accomplishments that have profoundly influenced the current direction of semiconductor science and technology.
“Mobile phone communications, satellite reception, quantum computation and high-efficiency multi-junction solar cells for electricity generation are just some of the exciting fields that exemplify the rich consequences of his work,” Yang continued. “We are so very proud to see Professor Gossard’s achievements and contributions, especially his pioneering development of molecular-beam epitaxy, recognized in this meaningful way.”
Noted Rod Alferness, dean of the College of Engineering at UCSB, “Professor Gossard’s work in the area of materials growth is at the foundation of ground-breaking scientific and technological advances in semiconductor molecular layered materials. He and colleagues have leveraged this work to make fundamentally new optoelectronic devices, including the lasers and high-speed electronics that make the global Internet possible. The application of his discoveries and inventions has profoundly touched the daily lives of people worldwide.”
“I am honored to join the group of other scientists, engineers and technologists who have previously received this award,” Gossard said. “I want to thank my family, teachers and colleagues for their huge contributions. And I am pleased by the recognition that the award bring to UC and especially to UCSB.”
Four UC Santa Barbara engineers have been elected to the National Academy of Inventors (NAI) for 2015. Recognized for their “highly prolific spirit of invention,” ECE Professors John Bowers & Umesh Mishra and Materials and Chemistry & Biochemistry Professors Craig Hawker & Galen Stucky are among the newest fellows elected by the organization.
They join 164 other new NAI members for 2015, bringing the total of NAI fellows to 582, representing more than 190 research universities and governmental and non-profit research institutions.
“Each of these prestigious members of our faculty have made discoveries and then translated them into applications that change the world, from energy efficiency in electronics, to innovative polymers, to life-saving biomedical technology,” commented Rod Alferness, dean of the UCSB College of Engineering. “Society is benefiting from their intellectual contributions right now, and their work propels us into a bright future. We are tremendously proud of the recognition by NAI.”
ECE Professor John Bowers
An expert in photonics and optoelectronics, electrical and computer engineering professor John Bowers’s research focuses on the use of light to transmit data. By integrating electronic and photonic elements on the same silicon-based chip, the next generations of computers and telecommunications devices will be able to receive and transmit data at much faster speeds and with a fraction of the energy that is being used today.
Bowers is the founding director of the UCSB Institute for Energy Efficiency and a cofounder of the campus’s Technology Management Program, as well as the West Coast lead for the federally funded American Institute for Manufacturing of Photonics. A veteran of industry who worked at Bell Laboratories and Honeywell before joining UCSB in 1987, Bowers has published 466 journal papers, received 54 patents and consults with numerous photonics manufacturing companies.
“It is very gratifying when new products or new companies come out of good research,” Bowers said of the “creative research” required to bring forth advanced technologies and bring them to the market.
Bowers is a member of the National Academy of Engineering, a fellow of the Institute of Electrical and Electronics Engineers, Optical Society of America (OSA) and the American Physical Society, and a recipient of the OSA Holonyak Prize.
ECE Professor Umesh Mishra
A whopping $40 billion in unused energy is wasted in the United States annually, and it’s not coming from the more obvious places in our energy infrastructure. Rather, the energy dissipation happens at the point of conversion, with the adaptors in our various devices changing the voltage that arrives through power outlets to be compatible with the smaller requirements of our machines, and losing the rest as heat.
Electrical and computer engineering professor Umesh Mishra has made it his mission to put an end to that waste of energy and money, and in doing so, help to update the country’s outdated and inefficient energy infrastructure. His research expertise is in gallium nitride (GaN) electronics, utilizing the fine control offered by the wide-bandgap semiconductor material over the flow of electrons, enabling more efficient power distribution in various industrial and commercial systems, as well as opening the way to better integration of renewable energy sources.
“The impact of gallium nitride-based electronics is to radically improve the efficiency for radio-frequency power generation used in wireless base stations and also all forms of power conversion including data servers, solar inverters and electric and hybrid car motor drives,” said Mishra, who is “honored” to be inducted into NAI. “This is an important step in the journey toward ultra-low wasted energy in these functions, which reduces cost, mitigates environmental impact and takes the shackles off system design while creating jobs.”
Mishra, who joined UCSB in 1990, is a member of the campus’s Solid State Lighting & Energy Electronics Center and holds the Donald W. Whittier Chair in Electrical Engineering. He is also leading research efforts as part of PowerAmerica, a federally funded national research and manufacturing consortium established to accelerate research and development of GaN and other wide-bandgap semiconductor technologies.
Signal Compression Lab (SCL) alumni Jingning Han, Ankur Saxena, and Vinay Melkote, awarded the 2015 IEEE Signal Processing Society Young Author Best Paper Award
They were awarded for their journal paper “Jointly Optimized Spatial Prediction and Block Transform for Video and Image Coding”. The paper was co-authored with their Signal Compression Lab (SCL) advisor Professor Ken Rose.
The award will be given during the 2016 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP) in Shanghai, China.
The fundamentally new transistor employs atomically-thin semiconducting channel material and quantum mechanical tunneling, operates at a supply voltage of only 0.1 V with high ON/OFF current ratio, and lowers power dissipation by over 90% compared to the state-of-the-art silicon transistors
Members from ECE’s Nanoelectronics Research Lab, in collaboration with materials researchers at Rice University, have designed and demonstrated a breakthrough tunnel-field-effect-transistor (TFET) that displays very steep turn-on characteristics (or low subthreshold swing) leading to switching operation at only 0.1 V, and reduces power dissipation by more than 90% compared to conventional field-effect transistors (MOSFETs).
The new transistor allows highly efficient quantum mechanical phenomenon of band-to-band tunneling by exploiting the electronic properties of a judiciously designed vertical van der Waals heterostructure formed with germanium acting as source and substrate, and a two-dimensional (2D) semiconductor- molybdenum disulphide or MoS2 as the channel material.
The newly demonstrated TFET, reported in Nature, is the first device to satisfy the international technology roadmap for semiconductors (ITRS) specifications for tunnel-FETs at a low voltage of 0.1 V and could potentially revolutionize future electronics, including low-power computing, RF/analog circuits, as well as low-power biosensors and gas sensors. Professor Banerjee who directs the Nanoelectronics Research Lab, led this research.
UCSB College of Engineering:
“Nanoelectronics Engineers Develop Transistor that Overcomes Fundamental Power Limitations”
“Tunnel Transistor may Meet Power Needs of Future Chips”
Nanoelectronics Research Lab (NRL)
Klamkin and UC, Santa Barbara awarded for proposal on “PICULS: Photonic Integrated Circuits for Ultra-Low Size, Weight and Power”
NASA has selected 15 university-led proposals for the study of innovative, early stage technologies that address high priority needs of America’s space program.
The Early Stage Innovations awards from NASA’s Space Technology Research Grants Program are worth as much as $500,000 each. Universities have two to three years to work on their proposed research and development projects.
“The agency’s space technology research areas lend themselves to the innovative approaches U.S. universities can offer for solving tough science and exploration challenges,” said Steve Jurczyk, associate administrator for NASA’s Space Technology Mission Directorate in Washington. “NASA’s Early Stage Innovations grants align with NASA’s Space Technology Roadmaps and the priorities identified by the National Research Council, helping enable NASA’s exploration goals including robotic missions to Mars and the outer planets, and ultimately human exploration of Mars.”
The proposals selected under the Early Stage Innovations 2015 solicitation address unique, disruptive or transformational technologies, including: payload technologies for assistive free-flyers; robotic mobility technologies for the surfaces of icy moons; integrated photonics for space optical communication; computationally guided structural nanomaterials design; and atmospheric entry modeling development using flight data from the Orion’s first flight test in space last December called Exploration Flight Test 1 (EFT-1).
David Auston, executive director of UC Santa Barbara’s Institute for Energy Efficiency, Center for Energy Efficient Materials and ECE Adjunct Professor, is among 10 University of California faculty members to receive the award from UC President Janet Napolitano
The award recognizes Auston and faculty members from UCLA, UC San Diego, UC Davis, UC San Francisco and UC Santa Cruz for demonstrating outstanding leadership on UC President Janet Napolitano’s systemwide initiatives. They range from increasing student access and diversity, enhancing campus entrepreneurialism, achieving carbon neutrality, promulgating healthy and sustainable food systems around the world and furthering UC’s engagement with Mexico.
Auston is a member of Napolitano’s Global Climate Leadership Council and co-chair of the council’s Applied Research Working Group. Within months of the creation of the council, he helped to convene two workshops on how UC research could be deployed to help meet the systemwide goal of achieving carbon neutrality by 2025. He also played a leading role in organizing a carbon neutrality research summit that included Napolitano, Gov. Jerry Brown and other state leaders, top administrators, sustainability managers and researchers from UC.
“This is a very special honor,” said Auston. “It has been — and continues to be — a great pleasure to work with all the members of the Global Climate Leadership Council and the many faculty, staff and students from the 10 UC campuses, the three national laboratories and UCOP, who are workingto advance the Carbon Neutrality Initiative.”
The award selection committee credited the paper for being judged the most influential on research and industrial practice in computer-aided design of integrated circuits over the ten years since its original appearance at ICCAD
At the recently concluded 34th IEEE/ACM International Conference on Computer Aided Design (ICCAD), held in Austin, Texas, the executive committee of the conference presented the prestigious ICCAD 2015 Ten Year Retrospective Most Influential Paper Award to Professor Kaustav Banerjee and ECE alum, Dr. Navin Srivastava.
For over 34 years, ICCAD has been the world’s premier conference devoted to technical innovations in electronic design automation. The selected paper that was published in the 2005 Proceedings of ICCAD is titled “Performance Analysis of Carbon Nanotube Interconnects for VLSI Applications.” The article’s co-author, Dr. Navin Srivastava, carried out his doctoral research in Professor Banerjee’s Nanoelectronics Research Lab and received the PhD degree in Spring 2009. He is currently an R&D engineer at Mentor Graphics Corporation, Wilsonville, Oregon.
The semiconductor industry has been looking for alternative interconnect solutions to replace copper due to their increasing resistivity and limited current carrying capacity. Professor Banerjee’s early work highlighting the prospects of carbon nanomaterials (including carbon nanotubes and graphene nano-ribbons) as interconnects and passives is now being pursued in many industrial R&D labs and research groups around the world.
UCSB researchers take aim at the potential bottleneck created by the growing flood of shared multimedia content on wireless networks
“According to industry projections that are widely quoted, mobile broadband data demand will grow by a thousandfold between 2010 and 2020,” says Upamanyu Madhow, a professor in UC Santa Barbara’s Department of Electrical and Computer Engineering. “We are in the middle of this period, and wireless carriers and equipment providers are scrambling to come up with solutions.” The demand, he said, is driven by bandwidth-hungry multimedia applications, such as streaming services, games and cloud storage, as well as web conferencing and remote desktop services. Should the network become overloaded, Madhow noted, users of these apps would experience the familiar and very frustrating slowdown of service.
However, with the help of $2.4 million in funding from the National Science Foundation, Madhow and fellow UCSB researchers Jim Buckwalter, Mark Rodwell and Heather Zheng, along with Amin Arbabian of Stanford University and Xinyu Zhang of the University of Wisconsin-Madison, plan to investigate an emerging approach to wireless connectivity. Their research focuses on what is called the “millimeter wave band,” an area of the electromagnetic spectrum that operates at a much higher frequency than the radio waves used in conventional wireless communications.
Schow elected for his contributions to high capacity optical interconnects
OSA Fellows are selected based on their overall impact on optics, as gauged through factors such as specific scientific, engineering, and technological contributions, a record of significant publications or patents related to optics, technical leadership in the field, business leadership, and service to OSA and the global optics community.
Drawing from nominations from current fellows, the OSA Fellow Members Committee recommends candidates to the OSA Board of Directors. This process is highly competitive, as no more than 10 percent of the OSA Membership may be Fellows.