us dept of edu
Xiaolin Tang: In Memoriam
We are deeply saddened at the passing of our student, colleague, and friend, Xiaolin Tang. Her passing is a tragedy, and she will be missed by all of us in the Physics and Astronomy Department. She was bright, talented, and eager to make an impact on the world. Since joining our graduate program, she had an impressive research record in biophysics and biochemistry, and was an avid participant and award winner in our Student Research Symposium.
It is a great loss to the scientific community that we will never have the opportunity to see her work progress or know the contributions she would have made to advance our field. Our thoughts and deepest condolences are with her family and friends at this very difficult time.
All of our students are very important to us. We want all the members of our community to know that there is support for you in this time of tragedy. This includes the University Counseling Center, and the Employee Assistance Program (contact information for both resources are listed below). Our colleagues at University of Utah Health also provided a helpful online resource for understanding and coping with grief that is available here: https://healthcare.utah.edu/caring-connections/understanding-grief.
University Counseling Center (for all students)
426 Student Services Building (map)
Employee Assistance Program (for faculty and staff)
801-587-9319 or 1-800-926-9619
Frontiers of Science with Dr. Robert Hazen
Thursday, December 7, 2017 @ 6:00 p.m. – Frontiers of Science with Dr. Robert Hazen! “The Story of Earth: How Life and Rocks Co-evolved” in room 220 of the Aline Wilmot Skaggs Building (ASB) on the U of U Campus!
FRONTIERS OF SCIENCE
with Dr. Robert Hazen,
Senior Staff Scientist at the Carnegie Institution’s Geophysical Laboratory Clarence Robinson Professor of Earth Science at George Mason University
Date Time: Thursday, December 7, 2017 at 6:00pm
The story of Earth is a 4.5-billion-year saga of dramatic transformations, driven by physical, chemical, and—based on a fascinating growing body of evidence—biological processes. The co-evolution of life and rocks, the new paradigm that frames this lecture, unfolds in an irreversible sequence of evolutionary stages. Each stage re-sculpted our planet’s surface, each introduced new planetary processes and phenomena, and each inexorably paved the way for the next. This grand and intertwined tale of Earth’s living and non-living spheres is only now coming into focus.
Frontiers of Science is free and open to the public. The Frontiers lecture series features eminent scientists and researchers from across the country who are exploring the latest frontiers in their fields. All lectures are free and open to the public, although tickets are required and seating is limited. Click here to learn more about the Frontiers of Science lecture series.
University of Utah researchers develop milestone for ultra-fast communications and computing
PHOTO CREDIT: Dan Hixon/University of Utah College of Engineering
U physics astronomy Distinguished Professor Valy Vardeny, left, and U electrical and computer engineering professor Ajay Nahata have discovered that a special kind of perovskite, a combination of an organic and inorganic compound.
A mineral discovered in Russia in the 1830s known as a perovskite holds a key to the next step in ultra-high-speed communications and computing.
Researchers from the University of Utah’s departments of electrical and computer engineering and physics and astronomy have discovered that a special kind of perovskite, a combination of an organic and inorganic compound that has the same structure as the original mineral, can be layered on a silicon wafer to create a vital component for the communications system of the future. That system would use the terahertz spectrum, the next generation of communications bandwidth that uses light instead of electricity to shuttle data, allowing cellphone and internet users to transfer information a thousand times faster than today.
The new research, led by University of Utah electrical and computer engineering professor Ajay Nahata and physics and astronomy Distinguished Professor Valy Vardeny, was published Monday, Nov. 6 in the latest edition of Nature Communications.
The terahertz range is a band between infrared light and radio waves and utilizes frequencies that cover the range from 100 gigahertz to 10,000 gigahertz (a typical cellphone operates at just 2.4 gigahertz). Scientists are studying how to use these light frequencies to transmit data because of its tremendous potential for boosting the speeds of devices such as internet modems or cell phones.
Nahata and Vardeny uncovered an important piece of that puzzle: By depositing a special form of multilayer perovskite onto a silicon wafer, they can modulate terahertz waves passing through it using a simple halogen lamp. Modulating the amplitude of terahertz radiation is important because it is how data in such a communications system would be transmitted.
Previous attempts to do this have usually required the use of an expensive, high-power laser. What makes this demonstration different is that it is not only the lamp power that allows for this modulation but also the specific color of the light. Consequently, they can put different perovskites on the same silicon substrate, where each region could be controlled by different colors from the lamp. This is not easily possible when using conventional semiconductors like silicon.
“Think of it as the difference between something that is binary versus something that has 10 steps,” Nahata explains about what this new structure can do. “Silicon responds only to the power in the optical beam but not to the color. It gives you more capabilities to actually do something, say for information processing or whatever the case may be.”
Not only does this open the door to turning terahertz technologies into a reality — resulting in next-generation communications systems and computing that is a thousand times faster — but the process of layering perovskites on silicon is simple and inexpensive by using a method called “spin casting,” in which the material is deposited on the silicon wafer by spinning the wafer and allowing centrifugal force to spread the perovskite evenly.
Vardeny says what’s unique about the type of perovskite they are using is that it is both an inorganic material like rock but also organic like a plastic, making it easy to deposit on silicon while also having the optical properties necessary to make this process possible.
“It’s a mismatch,” he said. “What we call a ‘hybrid.’”
Nahata says it’s probably at least another 10 years before terahertz technology for communications and computing is used in commercial products, but this new research is a significant milestone to getting there.
“This basic capability is an important step towards getting a full-fledged communications system,” Nahata says. “If you want to go from what you’re doing today using a modem and standard wireless communications, and then go to a thousand times faster, you’re going to have to change the technology dramatically.”
The paper was co-authored by students, Ashish Chanana, Yaxin Zhai, Sangita Baniya and Chuang Zhang.