Synopsis

A Possible Quantum Computing Boost 

Physics 11, s145
A hybrid quantum-classical computing algorithm could solve a basic computer science problem faster than a classical computer.
V. Dunjko/Leiden University

As companies race to build bigger quantum computers, it’s still unclear what near-term devices made of 100 qubits or less will be good for. Searching for applications, researchers are developing algorithms where quantum computing could boost performance. Now, Vedran Dunjko of Leiden University in the Netherlands and colleagues show that a small quantum computer can speed up an algorithm for solving the so-called 3SAT problem, a basic problem that is difficult for classical computers.

The 3SAT problem is a type of basic logic puzzle that tries to find values for some number of Boolean variables in an equation such that given combinations of groups of three return a true value. These problems show up in optimization algorithms such as scheduling and planning tasks, as well as statistical physics. However, classical computers likely cannot solve them efficiently with brute-force methods.

The researchers based their quantum method on a classical solution for solving 3SAT problems known as Schöning’s algorithm. They found that the quantum algorithm boosts performance only if the number of Boolean variables does not exceed a threshold that depends on the number of qubits in the computer. Thus they propose a quantum-classical hybrid algorithm that first reduces the number of variables on a classical computer and then switches to a quantum computer when the number of variables reaches the threshold. However, the researchers point out that the algorithm assumes error-corrected qubits, which hardware developers have not achieved yet. To implement the algorithm on near-term devices, the researchers say it would need to be further tailored to specific hardware.

This research is published in Physical Review Letters.

–Sophia Chen

Sophia Chen is a freelance science writer based in Tucson, Arizona.


Subject Areas

Quantum Information

Related Articles

Pushing the Limits of Quantum Sensing with Variational Quantum Circuits
Quantum Information

Pushing the Limits of Quantum Sensing with Variational Quantum Circuits

Variational quantum algorithms could help researchers improve the performance of optical atomic clocks and of other quantum-metrology schemes. Read More »

Using Quantum Dots to Simulate Magnetism
Quantum Physics

Using Quantum Dots to Simulate Magnetism

Researchers successfully use an array of quantum dots to create and study a Heisenberg spin chain. Read More »

Quantum Leap for Quantum Primacy
Quantum Physics

Quantum Leap for Quantum Primacy

Two experimental quantum computers tackle the most complex problems yet, suggesting an end to the debate on whether quantum “primacy”—the point at which a quantum computer outperforms the best possible classical computer—can be reached. Read More »

More Articles