Efficient quantum computing is expected to enable advancements that are impossible with classical computers. Scientists from Japan and Sydney have collaborated and proposed a novel two-dimensional design that can be constructed using existing integrated circuit technology. This design solves typical problems facing the current three-dimensional packaging for scaled-up quantum computers, bringing the future one step closer.

Quantum computing is increasingly becoming the focus of scientists in fields such as physics and chemistry, and industrialists in the pharmaceutical, airplane, and automobile industries. Globally, research labs at companies like Google and IBM are spending extensive resources on improving quantum computers, and with good reason. Quantum computers use the fundamentals of quantum mechanics to process significantly greater amounts of information much faster than classical computers. It is expected that when error-corrected and fault-tolerant quantum computation is achieved, scientific and technological advancement will occur at an unprecedented scale.

But building quantum computers for large-scale computation is proving to be a challenge in terms of their architecture. The basic units of a quantum computer are the “quantum bits” or “qubits.” These are typically atoms, ions, photons, subatomic particles such as electrons, or even larger elements that simultaneously exist in multiple states, making it possible to obtain several potential outcomes rapidly for large volumes of data. The theoretical requirement for quantum computers is that these are arranged in two-dimensional (2-D) arrays, where each qubit is both coupled with its nearest neighbor and connected to the necessary external control lines and devices. When the number of qubits in an array is increased, it becomes difficult to reach qubits in the interior of the array from the edge. The need to solve this problem has so far resulted in complex three-dimensional (3-D) wiring systems across multiple planes in which many wires intersect, making their construction a significant engineering challenge.