‘Perfect entanglement’ of two light beams has opened a major step towards highly secure quantum communication systems.
The University of Queensland’s Professor Tim Ralph and his colleagues from Canada and Russia have developed a technique to restore entangled light beams that have been distributed between distant points.
The design of a 3D silicon chip architecture clears another hurdle in the international race to build quantum computers.
Researchers at the University of Melbourne and the University of New South Wales (UNSW) have designed a chip based on single atom quantum bits, creating a blueprint for building a large-scale silicon quantum computer.
Sending quantum messages over long distances will be challenging. The signal will have to be amplified every few hundred kilometres, but conventional optical amplification would destroy the quantum message.
In a quantum information system, if you measure the light, you will destroy the information encoded on it. You need to store the light itself.
“We have to catch and store the light, but we’re not allowed to look at it to see what information it contains. If the system is working, the light will be exactly the same when we let it out again. We do this by absorbing the light into a cloud of atoms,” says Dr Ben Buchler.
The development of a two-quantum bit (qubit) logic gate in silicon heralds the possibility of moving quantum computers from experimental lab to large-scale manufacture much faster than other global research efforts.
Scientia Professor Andrew Dzurak and his team have created a two-qubit gate – a critical component, which allows qubits to talk to each other and will form the basis for a quantum computer chip.
It’s an advance that the UK’s premier physics magazine, Physics World, declared one of the top 10 breakthroughs of 2015.
Across the world, the race is on to develop the first quantum computer and an Australia research centre is at the front of the pack.
The Australian Government, Telstra and the Commonwealth Bank of Australia have recently recognised the pole position of the ARC Centre of Excellence for Quantum Computation and Communication Technology (CQC2T) by investing $46 million towards a targeted goal of realising a 10-qubit quantum integrated circuit in silicon within the next five years.
In this feature we explore some of the Centre’s advances in quantum information research.
Physicists at the University of New South Wales are leading the race to build computers exponentially faster than any we currently use, according to an assessment published by the scientific journals group, Nature.
Quantum memory has been extended to six hours in an advance that brings the spirit of the Pony Express to quantum communications, raising the prospect of physical transport of ‘read once’ quantum ‘memory sticks’.