A Fredkin gate has been developed, for the first time in history, by researchers from the University of Queensland and Griffith University. The development could bring quantum computers closer to reality.
A quantum Fredkin Gate simplifies a complex logic operations withing logic gates similar to those employed by contemporary computing systems.
"The allure of quantum computers is the unparalleled processing power that they provide compared to current technology. Much like our everyday computer, the brains of a quantum computer consist of chains of logic gates, although quantum logic gates harness quantum phenomena," said Raj Patel from the Centre for Quantum Dynamics at Griffith University.
In order for practical quantum computers to be developed, researchers must develop methods to process information, while utilizing as few logic gates as possible. The use of many small gates is akin to building a large wall using large numbers of small pieces of wood. Larger logic gates would allow processors constructed from fewer pieces, in the same way that panels may be used to quickly construct a wall.
Digital computers process information as a series of ones and zeroes, which are sent through gates, performing operations such as "and," "or," and "not." Quantum computers operate using quantum bits (qubits), numbers which can hold a strange mixture of the two values. Currently, such systems are challenging to produce, due to the vast numbers of gates which must be employed on each circuit.
A Fredkin gate can trade two values between qubits, based on a reading of a third.
The quantum entanglement of light is utilized in this first Fredkin gate to swap values between qubits. This function is required for several mathematical operations, including Shor's algorithm for finding prime numbers.
Numbers may also be compared to each other, an ability utilized in a wide range of digital applications. One eexample would be secure digital communications, ensuring sets of digital signatures are identical.
Researchers believe their work may be expanded to larger circuits, heralding the age of quantum computers. Such processors could be tens of thousands, or even a million times faster than today's systems. Such revolutionary processors could accurately predict the weather and climate, run vast simulations speeding testing of new medicines, and much more.
Development of the world's first Fredkin gate was published in the journal Science Advances.