By firing a Fibonacci laser pulse at atoms inside a quantum computer, physicists have created an entirely new, strange phase of matter that behaves as if it had two dimensions of time.

Including a theoretical “extra” time dimension “is a completely different way of thinking about phases of matter,” lead author Philipp Dumitrescu, a researcher at the Flatiron Institute’s Center for Computational Quantum Physics in New York City. said in a statement . “I worked for these THEORY ideas for over five years and to see them actually come to fruition in experiments is exciting.”

Connected: The otherworldly ‘time crystal’ made inside Google’s quantum computer could change physics forever

Physicists did not attempt to create a phase with a theoretical extra time dimension, nor were they looking for a method to enable better storage of quantum data. Instead, they were interested in creating a new phase of matter—a new form in which matter can exist, beyond the standard solid, liquid, gas plasma.

They began building the new stage in quantum computing company Quantinuum’s H1 quantum processor, which consists of 10 ytterbium ions in a vacuum chamber that are precisely controlled by lasers in a device known as an ion trap.

Ordinary computers use bits, or 0s and 1s, to form the basis of all calculations. Quantum computers are designed to use qubits, which can also exist in state 0 or 1. But that’s where the similarities end. Thanks to the strange laws of the quantum world, qubits can exist in a combination, or superposition, of both 0 and 1 states until the moment they are measured, after which they randomly collapse to either 0 or 1.

This strange behavior is key to the power of quantum computing, as it allows qubits to bind together quantum entanglement a process that Albert Einstein called “spooky action at a distance.” Entanglement pairs two or more qubits together, linking their properties so that any change in one particle causes a change in the other, even if they are separated by great distances. This gives quantum computers the ability to perform multiple calculations simultaneously, exponentially increasing their processing power over that of classical devices.

But the development of quantum computers is hampered by a major flaw: Qubits not only interact and entangle with each other; because they cannot be perfectly isolated from the environment outside the quantum computer, they also interact with the external environment, thereby causing them to lose their quantum properties and the information they carry, in a process called decoherence.

“Even if you keep it all ATOM under tight control, they can lose their ‘quantity’ by talking to their environment, heating up, or interacting with things in ways you didn’t plan for,” Dumitrescu said.

To overcome these pesky decoherence effects and create a new, stable phase, physicists looked to a special set of phases called topological phases. Quantum entanglement not only enables quantum devices to encode information through the singular, static positions of qubits, but also to interweave them in the dynamic motions and interactions of the entire material—in the very shape or topology of the material’s entangled states. . This creates a “topological” qubit that encodes information in the form formed by multiple parts rather than just one part, making the phase much less likely to lose its information.

A key sign of moving from one phase to another is the breaking of physical symmetries—the idea that the laws of physics are the same for an object at any moment in time or space. As a liquid, the molecules in water follow the same physical laws at every point in space and in every direction. But if you cool water enough that it turns into ice, its molecules will choose regular points along a crystal structure, or lattice, to arrange themselves. Suddenly, water molecules have preferred points in space to occupy, and they leave other points empty; the spatial symmetry of water is spontaneously broken.

The creation of a new topological phase within a quantum computer also relies on symmetry breaking, but with this new phase, the symmetry is not being broken in space, but in time.

Connected: The world’s first multinode quantum network is a breakthrough for the quantum internet

By giving each ion in the chain a periodic pulse with the lasers, the physicists wanted to break the continuous time symmetry of the ions at rest and impose their own time symmetry – where the qubits remain the same at certain intervals in time – which would create a rhythmic topological phase throughout the material.

But the experiment failed. Instead of inducing a topological phase that was immune to decoherence effects, regular laser pulses amplified noise from outside the system, destroying it less than 1.5 seconds after it was turned on.

After reexamining the experiment, the researchers realized that to create a more robust topological phase, they would need to incorporate more than one time symmetry into the array of ions to reduce the chances of the system mixing. To do this, they set out to find a pulse pattern that did not repeat simply and regularly, but nevertheless showed a higher kind of symmetry over time.

This led them to The Fibonacci sequence , in which the next number of the sequence is created by adding the previous two. While a simple periodic laser pulse can only alternate two laser sources (A, B, A, B, A, B, and so on), their new pulse train worked by combining the two pulses that came before ( A, AB, ABA, ABAAB, ABAABABA, etc.).

This Fibonacci pulsation created a time symmetry that, like a quasicrystal in space, was ordered without ever repeating itself. And just like a quasicrystal, Fibonacci pulses also imprint a higher dimensional pattern on a lower dimensional surface. In the case of a spatial quasicrystal like the Penrose plate, part of a five-dimensional lattice is projected onto a two-dimensional surface. When we look at the Fibonacci pulse pattern, we see that two theoretical time symmetries flatten into a single physical one.

An example of pen tiles (Image credit: Shutterstock)
“The system essentially gets a bonus symmetry from a non-existent dimension of extra time,” the researchers wrote in the statement. The system appears as a material that exists in a higher dimension with two time dimensions – even if this may be physically impossible in reality.

When the team tested it, the new quasiperiodic Fibonacci pulse created a topographic phase that protected the system from data loss throughout the 5.5 seconds of the test. Indeed, they had created a phase that was immune to decoherence for much longer than others.

“With this quasi-periodic sequence, there is a complicated evolution that cancels out all the errors that live on the edge,” Dumitresku said. “Because of this, the edge stays quantum-mechanically coherent much, much longer than you’d expect.”

Although the physicists achieved their goal, one hurdle remains in making their phase a useful tool for quantum programmers: integrating it with the computational side of quantum computing so that it can be embedded with calculations.

“We have this straightforward, enticing application, but we have to find a way to pin it down in calculations,” Dumitresku said. “This is an open problem that we are working on.”

Originally published in Live Science.