A research team from the Japan Institute of Molecular Science has taken a major step forward in quantum computing, making it a reality with the help of a two-qubit gate. A qubit is the quantum equivalent of a binary bit, which is a basic unit of information used in computing.
The team managed to successfully run the world’s fastest two-qubit gate in just 6.5 nanoseconds. In the process, the researchers had to overcome some of the limitations linked to this type of technology. However, there is a catch: the method they used might be difficult to replicate in a less research-based environment.
Quantum computing is still somewhat uncharted territory, but it could be the gateway to solving problems that modern computers can’t tackle. It could also greatly speed up high-performance computing (HPC) tasks. While the potential is definitely there and tech giants like IBM and Intel are taking advantage of it, the limitations are also there, which is why research teams around the world continue to explore the topic.
The team of scientists from the Institute of Molecular Sciences, led by graduate student Yeelai Chew, Assistant Professor Sylvain de Léséleuc, and Professor Kenji Ohmori, conducted the research and published their findings. findings in Nature Photonics. The two-qubit gate operation they were able to execute is an early but important step. Tom’s Hardware was one of the first publications to detail the process after the initial article in Nature appeared online.
The researchers used lasers to drastically cool two atomic qubits.
Qubits are the quantum equivalent of bits that we are all familiar with from everyday computing. However, qubits come with an advantage: they are not limited to a value of one or zero; Instead, they can represent both one and zero. This makes them much more efficient and unlocks their ability to accomplish complex tasks in a much, much shorter period of time. Unfortunately, qubits quickly decohere, meaning they no longer return accurate results.
A two-qubit gate operation requires that the qubits be entangled, and this entanglement is affected by several factors that can speed up decoherence. The decoherence problem can be dealt with in two ways: the operations must be performed much faster, before the qubits decohere, or the entanglement must take longer. The science team went with the first approach, which was to speed things up drastically, and they did just that, achieving a world record in the process.
The researchers used lasers to drastically cool two atomic qubits made of the element Rubidium. Temperatures reached near absolute zero, dipping as low as -273.15 degrees Celsius. These atoms were secured within a micrometer of each other by using optical tweezers. They then used a laser to manipulate the qubits at 10-picosecond intervals. A picosecond is the equivalent of one trillionth of a second.
Through the above steps, the researchers were able to successfully execute a quantum gate in just 6.5 nanoseconds, making it the fastest two-qubit gate operation in the world. The previous record was 15 nanoseconds.
While this jump doesn’t mean that quantum computing is suddenly going mainstream, it does mean that scientists are making big strides in that direction. Unfortunately, this type of technology can be difficult to replicate in an HPC environment, which is where it would be most commonly used.
The rubidium atom qubits that were used by the researchers to run this ultrafast qubit gate must be cooled to near absolute zero for them to work. Doing so may be possible in special cases, but realistically most organizations would turn to a different solution until this can be easier to manage. On the other hand, even if this technology won’t become the gold standard one day, the research is important as scientists continue to try to determine where exactly the future of computing lies.