Scientists construct largest quantum 'circuit board' ever

Researchers have developed the world's largest quantum circuit board, an advance that will help develop the first quantum computer.
The 'circuit board' is an essential component for a quantum computer made of laser light.
The international collaboration with the University of Tokyo and the Australian National University saw the largest number of quantum systems brought together in a single component jump from 14 to 10,000.
"The transistor, invented in the mid-1940s, replaced vacuum tubes in ordinary computers with components that can be mass produced," said Dr Nicolas Menicucci, from the University of Sydney's School of Physics.
"The scalability afforded by transistors enabled the explosion in computing technology we've seen in the last 65 years.

"Similarly, this breakthrough promises scalable design of laser-light quantum computing hardware," Menicucci said.

A theoretical physicist, Menicucci proposed the experimental design, which was realised by researchers at the University of Tokyo, led by Professor Akira Furusawa.
A working quantum computer would exploit the mysterious properties of quantum physics, allowing the most difficult computational problems - impractical for even the fastest supercomputers - to become feasible to solve.
"The two main obstacles to creating quantum computers are the precise control of tiny quantum systems and the issue of scalability, which is the ability to make bigger and bigger quantum computers out of small parts," said Menicucci.

"We have made a breakthrough in scalability for the basic 'circuit board' of a quantum computer made out of laser light," Menicucci said.
The design proposed by Menicucci allowed Furusawa's research team to construct a 'circuit board' of more than 10,000 quantum systems - an increase of three orders of magnitude over the nearest competing design.
"This experiment now holds the world record for the largest quantum resource ever produced in which every part can be accessed directly and individually, which is essential if it is to be useful for quantum computing," Menicucci said.
The study is published in journal Nature Photonics.