Quantum computing will take off when we have higher quality qubits, and lasers are helping us get there
The challenges that quantum computing places before us they are titanic. During the last decade the research teams that are working in this discipline have reached surprising milestones, such as the much discussed quantum supremacy, but the researchers responsible for these innovations are the first to recognize that there is still a lot of work to do for quantum computers to help us solve some of the most pressing problems we face.
We need a robust error correction system, tools that help us control the qubits with precision, new quantum algorithms that respond to real needs, and, above all, higher quality qubits. The stability of qubits and their ability to protect quantum information and the operations we carry out with it largely depends on the viability of future quantum computers.
The power of a quantum computer is not only conditioned by the number of qubits with which it is capable of working; its quality is also crucial
Curiously, the power of a quantum computer is not only conditioned by the number of qubits with which it is capable of working; Its quality is also crucial, understood as the capacity of these qubits of not be disturbed by noise. In fact, qubits can spontaneously change their quantum state as a consequence of disturbances introduced by thermal energy.
This is the reason why current quantum computers use a very sophisticated cooling system that allows them to work at a very close temperature to absolute zero (-273.15 degrees centigrade). At this low temperature, the internal energy of the system is minimal, although it is not zero, so the probability that the qubits change state spontaneously is lower.
Lasers can help us protect extremely fragile quantum information
Research groups involved in the development of quantum computing are exploring various strategies that seek to help us obtain higher quality qubits, and one of the most promising is resort to lasers to enter and retrieve information from a set of qubits. Precisely some scientists from the University of Cambridge They have just obtained a very promising result that invites us to face the future of quantum computing with optimism.
What they have achieved is to introduce quantum information, which, as we have seen, is extremely fragile, in a conglomerate of 100,000 atomic nuclei. To achieve this they have resorted to a laser that has the necessary precision to act on a single electron of the conglomerate, and through which they have managed to control the behavior of the conglomerate as a whole.
These researchers say that using a laser is a successful strategy because it allows them to place quantum information in the system and retrieve it introducing minimal disturbance. In addition, the ability with which this technology allows them to control the behavior of the conglomerate as a whole makes it possible to retrieve quantum information with enormous precision, largely thanks to the almost total absence of disturbances.
The metaphor these researchers have used to explain how they have achieved control the entire conglomerate of nuclei acting on a single electron is very illustrative: «From a technical point of view this procedure is very complex. We do not know how we can ‘speak’ to the cluster, and it does not know how it can speak to us either, but we can communicate with a single electron that acts on the cluster in the same way that a dog controls a flock of sheep, ”says Professor Mete Atatüre.
By acting on the electron spin, which is a quantum magnitude, these researchers have managed to order the nuclei to introduce and retrieve quantum information
According to these researchers, the technology they are working on represents a very important step forward in the search for more robust qubits, and therefore capable of preserving quantum information for a longer time. But this is not all. They also ensure that their research lays the first brick of the foundation of the quantum internet that will facilitate the communication of quantum systems that we hope to have in the future.
Everything these researchers tell us, and what other scientists with whom we have had the chance to speak, reminds us of the enormous complexity that each advance in quantum computing entails, no matter how small. But it also invites us to look forward with optimism. We just have to look back for a moment to see where we were just ten years ago, and where are we now. The road we have traveled in a decade is amazing.
More information | University of Cambridge