Nav: Home

Virginia Tech researchers lead breakthrough in quantum computing

July 25, 2019

The large, error-correcting quantum computers envisioned today could be decades away, yet experts are vigorously trying to come up with ways to use existing and near-term quantum processors to solve useful problems despite limitations due to errors or "noise."

A key envisioned use is simulating molecular properties. In the long run, this can lead to advances in materials improvement and drug discovery. But not with noisy calculations confusing the results.

Now, a team of Virginia Tech chemistry and physics researchers have advanced quantum simulation by devising an algorithm that can more efficiently calculate the properties of molecules on a noisy quantum computer. Virginia Tech College of Science faculty members Ed Barnes, Sophia Economou, and Nick Mayhall recently published a paper in Nature Communications detailing the advancement.

Quantum computers are expected to be able to carry out certain kinds of calculations far more efficiently than the "classical" computers in use today. They are similar to classical computers, however, in that they run algorithms by applying sequences of logic gates -- in this case, "quantum gates," which together form quantum circuits -- to bits of information. For today's noisy quantum computers, the problem has been that so much noise would accumulate within a circuit that the computation would degrade and render any subsequent calculations inaccurate. Scientists have had difficulty designing circuits that are both shorter and more accurate.

The Virginia Tech team addressed this issue by developing a method that grows the circuit in an iterative way. "We start with a minimal circuit, then grow it as we add on logic gate after logic gate in short circuits until the computer finds the solution," said Mayhall, an assistant professor in the Department of Chemistry.

A second major benefit of the algorithm is that Barnes, Economou, and Mayhall designed it to adapt itself based upon the molecular system being simulated. Different molecules will dictate their own circuits, uniquely tailored to them.

The interdisciplinary collaboration between Virginia Tech's departments of Chemistry and Physics -- Barnes, Economou, and Mayhall and a team of graduate students and postdocs from both departments -- have received grants from the National Science Foundation and the U.S. Department of Energy totaling more than $2.8 million.

Virginia Tech and IBM recently established a partnership that gives the researchers access to IBM's quantum computing hardware. "Our team at Virginia Tech is really excited for the next steps in our work," said Economou, an associate professor in the Department of Physics, "which include implementing our algorithm on IBM's processors."
-end-


Virginia Tech

Related Quantum Computers Articles:

Hot qubits break one of the biggest constraints to practical quantum computers
A proof-of-concept published today in Nature promises warmer, cheaper and more robust quantum computing.
Future quantum computers may pose threat to today's most-secure communications
Quantum computers that are exponentially faster than any of our current classical computers and are capable of code-breaking applications could be available in 12 to 15 years, posing major risks to the security of current communications systems, according to a new RAND Corporation report.
Novel error-correction scheme developed for quantum computers
Experimental quantum computers are plagued with errors. Here Dr Arne Grimsmo from the University of Sydney and colleagues from RMIT and the University of Queensland offer a novel method to reduce errors in a scheme applicable across different types of quantum hardware.
FEFU scientists developed method to build up functional elements of quantum computers
Scientists from Far Eastern Federal University (FEFU, Vladivostok, Russia), together with colleagues from FEB RAS, China, Hong Kong, and Australia, manufactured ultra-compact bright sources based on IR-emitting mercury telluride (HgTe) quantum dots (QDs), the future functional elements of quantum computers and advanced sensors.
ORNL researchers advance performance benchmark for quantum computers
Researchers at the Department of Energy's Oak Ridge National Laboratory (ORNL) have developed a quantum chemistry simulation benchmark to evaluate the performance of quantum devices and guide the development of applications for future quantum computers.
Quantum computers learn to mark their own work
A new test to check if a quantum computer is giving correct answers to questions beyond the scope of traditional computing could help the first quantum computer that can outperform a classical computer to be realised.
Blanket of light may give better quantum computers
Researchers from DTU Physics describe in an article in Science, how--by simple means -- they have created a 'carpet' of thousands of quantum-mechanically entangled light pulses.
One step closer future to quantum computers
Physicists at Uppsala University in Sweden have identified how to distinguish between true and 'fake' Majorana states in one of the most commonly used experimental setups, by means of supercurrent measurements.
Dartmouth research advances noise cancelling for quantum computers
The characterization of complex noise in quantum computers is a critical step toward making the systems more precise.
Spreading light over quantum computers
Scientists at Linköping University have shown how a quantum computer really works and have managed to simulate quantum computer properties in a classical computer.
More Quantum Computers News and Quantum Computers Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Our Relationship With Water
We need water to live. But with rising seas and so many lacking clean water – water is in crisis and so are we. This hour, TED speakers explore ideas around restoring our relationship with water. Guests on the show include legal scholar Kelsey Leonard, artist LaToya Ruby Frazier, and community organizer Colette Pichon Battle.
Now Playing: Science for the People

#568 Poker Face Psychology
Anyone who's seen pop culture depictions of poker might think statistics and math is the only way to get ahead. But no, there's psychology too. Author Maria Konnikova took her Ph.D. in psychology to the poker table, and turned out to be good. So good, she went pro in poker, and learned all about her own biases on the way. We're talking about her new book "The Biggest Bluff: How I Learned to Pay Attention, Master Myself, and Win".
Now Playing: Radiolab

Uncounted
First things first: our very own Latif Nasser has an exciting new show on Netflix. He talks to Jad about the hidden forces of the world that connect us all. Then, with an eye on the upcoming election, we take a look back: at two pieces from More Perfect Season 3 about Constitutional amendments that determine who gets to vote. Former Radiolab producer Julia Longoria takes us to Washington, D.C. The capital is at the heart of our democracy, but it's not a state, and it wasn't until the 23rd Amendment that its people got the right to vote for president. But that still left DC without full representation in Congress; D.C. sends a "non-voting delegate" to the House. Julia profiles that delegate, Congresswoman Eleanor Holmes Norton, and her unique approach to fighting for power in a virtually powerless role. Second, Radiolab producer Sarah Qari looks at a current fight to lower the US voting age to 16 that harkens back to the fight for the 26th Amendment in the 1960s. Eighteen-year-olds at the time argued that if they were old enough to be drafted to fight in the War, they were old enough to have a voice in our democracy. But what about today, when even younger Americans are finding themselves at the center of national political debates? Does it mean we should lower the voting age even further? This episode was reported and produced by Julia Longoria and Sarah Qari. Check out Latif Nasser's new Netflix show Connected here. Support Radiolab today at Radiolab.org/donate.