Google Close To Making A ‘Universal’ Quantum Computer, Combines Analog And Digital Approaches
byShort Bytes: A universal quantum computer could be closer than we imagined. The researchers from Google and some leading universities have found a way to combine digital and analog approaches of quantum computing. Google is calling this method as “quantum annealing with a digital twist” and using the same, it has created an early protype of a device.
fter many years of research and innovation, IBM and D-Wave have been successful in creating functional quantum computers. IBM has even connected some of its quantum computing resources to the internet, allowing people to use them
However, these companies have been unable to create devices scalable to as many qubits
needed to solve the complex problems. In simpler words, researchers have not been able to create a quantum computer that would be capable of solving the problems out of the reach of today’s computers.
In a recent development that can change this scenario, a team of researchers from Google, the University of California and IKERBASQUE, the University of the Basque Country, and Basque Foundation for Science has successfully combined two leading approaches in one prototype machine, according to Nature
The first approach, the digital one, designs the quantum computer using qubits in a certain arrangement, just like classical bits make a microprocessor. Here, qubits are linked to each other using the gate model to create quantum logic gates. So, to carry out tasks on such computer the gates must be programmed in advance.
The other approach, the analog one, is also called adiabatic quantum computing. Here, the problem is fed to the qubits in ground state. The qubits gradually evolve and reach a soluton by shaping their collective quantum state.
Notably, as compared to the digital approach, the errors produced during analog quantum computing can’t be corrected in an effective manner.
The researchers have overcome this problem by combining both approaches and labelled the method as “quantum annealing with a digital twist”.
In the new device, logic gates control the adjacent qubits that “digitally guide them to a state that encodes the solution to a problem.”
“With error correction, our approach becomes a general-purpose algorithm that is, in principle, scalable to an arbitrarily large quantum computer,” says Alireza Shabani, a member of the Google team.
Currently, Google’s device is in early prototype stage. The research team hopes that in a couple of years we can witness devices with more than 40 qubits.
“At that point,” Shabani says, “it will become possible to simulate quantum dynamics that is inaccessible on classical hardware, which will mark the advent of ‘quantum supremacy’.”
For more information, visit Nature and Google Research.