With exceptional processing power and some wicked physics, quantum computers promise to answer new questions, create new materials and synthesize new drugs.
“It’s a true revolution in technology and human life,” says University of Florida physics professor Hai-Ping Cheng, who’s on the forefront of quantum research.
With a new $10.5 million quantum research grant and a proposal for an even bigger center, UF is preparing to be a major player in the field of quantum computing. But what is it, and why does it matter?
To answer those questions, we have to understand what quantum mechanics is. Here’s your quantum computing cheat sheet and sneak peak at UF’s future role in the game.
The basics
Physics is the set of laws that describes how things work. Physicists group these laws into different branches — let’s call them “books.” The book of laws for objects on the human-sized scale (things we see and interact with regularly) is called “classical mechanics.” Quantum mechanics is the book for microscopic things: molecules, atoms and things even smaller than atoms.
Why care about things we can’t see? For one, they teach us about the things we can. We can’t study magnets without understanding quantum mechanical “spin.” We also take advantage of some special properties and laws in the quantum world to do things that we can’t do in our world.
Tiny world, big surprises
In the domain of really really small things, the laws of physics are not the ones we’re used to. If quantum mechanics governed our world, we could run into any of the following scenarios:
- Superposition: A cat in a box with a bomb is both alive and dead at the same time before the box is opened.
- Tunneling: A dart flies right through the dartboard.
- Entanglement: If one twin breaks his leg, the other twin’s leg is also broken.
These properties are hard to conceptualize. They don’t seem right — because in our book, they aren’t. However, like it or not, that’s just the way quantum mechanics works. In fact, we’re so confident in these laws that we can design machines and systems specifically to make use of them.
What’s the point?
Physicists exploit quantum mechanics principles to lay the groundwork for everything from lasers to MRI machines, but the applications don’t stop there. In the past few decades, researchers have been attempting to build a new kind of computer that makes use of the superposition and entanglement properties. Currently, there are about a dozen prototypes around the world.
The machines are still in a very early stage of development. If they evolve into their theoretical potential, quantum computers will be able to solve problems that classical computers cannot. This concept of “quantum supremacy” comes from the otherworldly quantum properties that allow for unimaginable boosts in efficiency.
For tasks like breaking cybersecurity codes or finding the one chemical structure of a drug that will cure a disease, classical computers must try every solution one at a time. Quantum computers, with the help of superposition, would be able to test nearly all possible combinations simultaneously.
While the fantastic promises are only conceptual for the moment, progress has been made. A report in Nature in October claims to be the first to demonstrate quantum supremacy by solving in 200 seconds a problem that would take the fastest current computers 10,000 years. Though the finding has faced much criticism, it’s a testament to the field’s progress and potential.
Quantum computers will likely never replace current conventional computing for everyday tasks. But with faster processing speeds, much larger storage capacity, higher energy efficiency and a new method for problem solving, these new machines have the potential to address new questions on a new scale.
What’s the hold-up?
The main obstacle lies in the materials that are needed to create quantum computers.
“Right now, nobody knows what the best system is to make quantum computers. There are a lot of problems with the materials we are currently using,” said Cheng, the director of the Center for Molecular Magnetic Quantum Materials (M2QM) at UF.
Currently, quantum computers are constructed mainly of superconductors, which have to be cooled to nearly -460 °F — the coldest possible temperature. On top of that, there’s an issue of “decoherence,” which limits how long information can remain in the quantum state. After a certain number of operations, it breaks down, and the information is lost.
With materials more suited for these conditions, researchers could use quantum computers to reach new heights.
“That’s the sort of thing we’re doing: providing the high-tech materials that people will be able to invest effort into making quantum computers out of,” said Samuel Trickey, senior advisor and investigator of M2QM.
What’s next?
Aside from searching for new materials, UF researchers are experimenting with new ways to get a foot in the door of quantum computing.
“The National Science Foundation wants to put some real effort into supporting quantum information systems,” said Beverly Sanders, a professor in UF’s computer and information systems and engineering department. “They realize this is a very interdisciplinary problem, so instead of just giving people a bunch of little grants, they’re going to be supporting some larger institutes at about $5 million a year for five years.”
Her team was awarded a conceptualization grant in September to create a proposal for one of these quantum information systems centers, which would likely focus on a new field called quantum biology.
“There are some big questions in biology — really important molecules and chemical reactions — that are just not well understood, and they’re not really able to be answered with the techniques we currently have,” Sanders said.
The purpose of this conceptualization project is to create a community of people interested in quantum mechanical applications and to identify some key problems in biology that could be answered using quantum computing.
“Now that it’s marginally feasible, it’s time to push really hard on it,” Trickey said.
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