Quantum computers are constructed using qubits, which are the quantum analogs of classical bits. The functionality of qubits is dependent on quantum entanglement and the principle of superposition, which are both essential phenomena at the core of quantum computing.
In contrast to a bit, which can only take on one of these values, a qubit can exist as both a 0 and a 1, because to the property of superposition. Entanglement, on the other hand, causes delicate interactions between qubits, which can be thought of as a form of connecting. There are a variety of various ways that qubits can be realized in the physical world. For instance, qubits can be realized as photons that have two different polarizations or as ions that are trapped and controlled by an electric field.
Because of this, these machines are considerably superior to their conventional counterparts in the ability to solve certain sorts of issues, such as evaluating data, simulating drug interactions, or improving the logistics of supply chain operations. However, there is a barrier that must be overcome in order to realize their full potential. Keeping qubits, which are essential to the operation of a working quantum computer, in a stable state has proven to be rather difficult.
These devices are particularly susceptible to noise from the outside environment as well as specific interactions between qubits, both of which can cause them to lose their fragile quantum states. As a direct consequence of this, the construction of a quantum computer that is in complete working order has been extremely challenging.
Philipp Dumitrescu, who works at the Flatiron Institute’s Center for Computational Quantum Physics, explained in an interview that “even if you maintain all the particles under strict control, they can end up losing their ‘quantumness’ by talking to their surroundings, heating up, or engaging with things in unexpected ways.” Dumitrescu made this statement.
A group of physicists, which included Dumitrescu, Andrew Potter of the University of British Columbia in Vancouver, Romain Wasser of the University of Massachusetts at Amherst, and Ajesh Kumar of the University of Texas, Austin, put forward a theory that was used in a new experimental study that was published in Nature. Based on this theory, Dumitrescu and his collaborators were able to better preserve the quantum states of qubits. This study was published in Nature.
It is common knowledge that the interaction of qubits with a periodic electromagnetic pulse, which is analogous to a radio wave, can result in a more stable quantum state for the qubits. Theorists came to the conclusion that a particular shape to the light pulse could make qubits more robust by mathematically analyzing the interaction of qubits with a variety of light pulses and not restricting themselves to periodic shape. This analysis allowed the theorists to avoid the restriction of periodic shape. The team’s simulations indicate that the shape ought to be non-repeating, despite being ordered. For example, the patterns of Penrose tiling in mathematics (feature picture) and quasicrystals in physics come to mind.
“With this semi pattern, there is a complex development that cancels out all of the errors that live on the border [or edge of a system, which in this case is one-dimensional with point-like borders,” Dumitrescu explained. “As a result, the edge retains its quantum-mechanical integrity for far longer than you would expect.”
According to the results of their calculations, ions located at the ends of a chain of entangled qubits kept their quantum properties for a significantly longer period of time after being radiated with the pulse than they would have if the pulse had not been applied. This result was brought about by the fact that the mathematical description of this pair implied that they existed in one more time dimension than was actually the case.
According to Dimitriu Dumitrescu, “[making use of a ‘additional’ temporal dimension] is a fundamentally different way of thinking about the phases of matter.” “I have been working on these theory ideas for over five years, and it is thrilling to see them come truly be realized in trials.”
Honeywell’s H1 quantum computer, which is based on ten ytterbium ions and was employed by an experimental team led by Brian Neyenhuis of Honeywell Quantum Solutions, was utilized in order to put this hypothesis to the test.
They illuminated the qubits with two different laser pulse sequences: the first sequence was periodic, and the second pattern was the one that was suggested by the theorists. In the instance of periodicity, the edge qubits maintained the required entangled quantum state for around 1.5 seconds, which is a highly respectable length of time for a quantum computer. The qubits, on the other hand, were able to maintain their quantum states throughout the entirety of the experiment, which lasted approximately 5.5 seconds thanks to the quasi-periodic pattern.
The conclusion drawn from these findings is that the recently uncovered qubit state has the potential to provide a more stable basis for quantum computing. However, researchers still need to comprehend how to implement their discovery into the actual algorithms of a quantum computer.
Theorists projected that higher-dimensional quantum systems could be even more error-resistant than the one-dimensional system that was used to obtain such an outstanding result; however, the one-dimensional system was used. The authors of the current study have high hopes that their work will prove to be a significant step forward in the process of putting these theoretical findings into actual practice.