Scientists from Yale’s Devoret research group have made a significant breakthrough in quantum computing by extending the lifetime of a qubit by 2.3 times, marking beyond the break-even point. The researchers improved the qubit’s coherence time: how long it can retain its quantum state before losing coherence and collapsing into classical bits. By extending the coherence time, the researchers have improved the qubit’s ability to preserve information and perform a more significant number of operations within a single lifetime.
The Devoret research group at Yale has achieved a significant advancement in quantum computing by extending the lifetime of a qubit beyond the break-even point. This development leads to higher preservation of information and allows for more operations to be performed on a qubit within its lifetime. To accomplish this breakthrough, the researchers utilized quantum error correction, a technique that protects information encoded in qubits from errors resulting from quantum noise.
Furthermore, machine learning was used to optimize calibration and precision, which led to a more precise and efficient error correction process. Using the Gottesman-Kitaev-Preskill quantum error correction code allowed the group to correct more errors than errors produced in quantum information, a significant achievement in the field.
This achievement is a critical step in developing practical quantum computers, which rely on stable and reliable qubits to perform complex calculations.
“We increased the lifetime by a factor of 2.3, so we more than doubled the number of operations that we can perform before the qubit begins to fail.”
Luigi Frunzio, a senior research scientist in applied physics
Extending the Lifetime of a Qubit Beyond the Break-Even Point
Before this study, many research groups worldwide had approached the break-even point, as Steve Girvin, Eugene Higgins professor of physics at Yale stated. Girvin further explained that this breakthrough was achieved through interdisciplinary research efforts and the accumulation of progress made over the years. As a result, this study became the first to extend the lifetime of a qubit beyond the break-even point and produce a gain greater than one.
The researchers utilized machine learning to optimize calibration and precision and applied quantum error correction to protect information encoded in qubits from errors due to quantum noise. The Gottesman-Kitaev-Preskill quantum error correction code enabled the research group to correct more errors than it produced in quantum information, a significant breakthrough in the field.
Baptiste Royer, the former postdoctoral student in the Devoret research group, noted that having a stable qubit above the break-even point indicates that the theories behind quantum computing are plausible. This achievement has significant implications for the field of quantum computing, and it could lead to the development of more stable and reliable quantum computers.
“One of the main claims is to show that it is possible to have a stable qubit above break-even at the heart of quantum error correction.”
Baptiste Royer, former postdoctoral student in the Devoret research group
Quantum computing takes a leap towards practicality with the recent breakthrough.
According to sources interviewed by the News, the recent breakthrough represents progress towards constructing more operational quantum computers. It also serves as a proof-of-principle demonstration that implies researchers may eventually build a quantum computer that outperforms any modern supercomputer. Even though quantum computers have yet to catch up to classical computers in terms of practicality, Girvin states that this breakthrough is a critical initial step in improving the functionality of quantum computers.
“This is a big step forward, though, there is still a huge distance to go to get a gain of millions or billions,” Girvin said. “But the journey to a billion begins with being above one. The grand challenge to solve is if quantum computers are going to be practical.”
Steve Girvin, Yale’s Eugene Higgins Professor of Physics
In pursuit of this objective, all three researchers have acknowledged the need for further progress to validate the practicality of quantum computing and quantum error correction. Specifically, they aim to extend the lifetime of qubits to a scale of billions and enable the implementation of complex algorithms by extending this breakthrough to multiple qubits. Royer emphasized this aspect of their research, highlighting the potential for significant advancements in quantum computing.
“With the feasibility of quantum error correction, better qubits and better machines altogether, quantum computation will not only be possible but also more concretely useful for disciplines beyond science and math.”
Luigi Frunzio, Senior Research Scientist in Applied Physics.
Read more about it here.