Quantum computing breakthrough: a phase of matter that exists in two time dimensions

The discovery offers a way of storing quantum information that is less prone to errors.
Loukia Papadopoulos

Scientists with funding from the Simons Foundation produced a phase of matter that behaves as if it exists in two time dimensions, according to a press release by the institution published on Wednesday. The researchers created the strange material by shining a sequence of laser pulses inspired by the Fibonacci numbers at atoms inside a quantum computer.

Data protected against errors

Information stored in the strange new phase of matter is far more protected against errors than information stored with the conventional setups currently used in quantum computers. The data can survive for much longer before becoming garbled, potentially making quantum computing viable, said study lead author Philipp Dumitrescu.

The use of a novel “extra” time dimension “is a completely different way of thinking about phases of matter,” said Dumitrescu, who worked on the project as a research fellow at the Flatiron Institute’s Center for Computational Quantum Physics in New York City. “I’ve been working on these theory ideas for over five years, and seeing them come actually to be realized in experiments is exciting.”

Quantum computers use elements called qubits to store and handle information, but there's a problem with that. Interacting with these qubits messes with their states leading to problems and errors.

Quantum computing breakthrough: a phase of matter that exists in two time dimensions
Source: DKosig

"Even if you keep all the atoms under tight control, they can lose their quantumness by talking to their environment, heating up or interacting with things in ways you didn’t plan,” Dumitrescu said. “In practice, experimental devices have many sources of error that can degrade coherence after just a few laser pulses.”

The scientists were therefore looking for ways to make these qubits more robust. To achieve that, physicists can use properties that hold up to change such as ‘symmetries."

The creation of a quasicrystal in time rather than space

Dumitrescu and his team used the creation of a quasicrystal in time rather than space and proceeded to develop a quasi-periodic laser-pulse regimen based on the Fibonacci sequence.

"In such a sequence, each part of the sequence is the sum of the two previous parts (A, AB, ABA, ABAAB, ABAABABA, etc.). This arrangement, just like a quasicrystal, is ordered without repeating. And, akin to a quasicrystal, it’s a 2D pattern squashed into a single dimension. That dimensional flattening theoretically results in two time symmetries instead of just one: The system essentially gets a bonus symmetry from a nonexistent extra time dimension," explained the institution's statement.

Further tests undertaken by the physicists demonstrated that the new phase of matter can act as long-term quantum information storage. However, the researchers still need to functionally integrate the phase with the computational side of quantum computing.