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A report published in Christian Science Monitor said, "Scientists, governments, and large corporations seek powerful computers for a number of activities from modeling air traffic control and molecular compositions to predicting weather events and ...
Advancement in Fredkin gate termed as big leap for Quantum Computing
Written by John DiPietro on 27 Mar 2016
The current project involving simplified Fredkin gate has been developed by researchers at Griffith University and the University of Queensland. The research paper has been published in the journal Science Advances.
Fredkin gates represent a small part of quantum computing circuit. Two quantum bits can be swapped or changed on the basis of third value in a quantum computer circuit. The research team has been successful in creating Fredkin gate in which the number of logic operations has been reduced. The research team has used particles of light.
The project team is a part of the Australian Research Council's Centre for Quantum Computation and Communication Technology. The aim of the project is to improve Australian expertise in quantum computing.
"The allure of quantum computers is the unparalleled processing power that they provide compared to current technology," said Dr Raj Patel from Griffith's Centre for Quantum Dynamics.
"Much like our everyday computer, the brains of a quantum computer consist of chains of logic gates, although quantum logic gates harness quantum phenomena."
The main stumbling block to actually creating a quantum computer has been in minimising the number of resources needed to efficiently implement processing circuits.
"Similar to building a huge wall out lots of small bricks, large quantum circuits require very many logic gates to function. However, if larger bricks are used the same wall could be built with far fewer bricks," said Dr Patel.
"We demonstrate in our experiment how one can build larger quantum circuits in a more direct way without using small logic gates."
At present, even small and medium scale quantum computer circuits cannot be produced because of the requirement to integrate so many of these gates into the circuits. One example is the Fredkin (controlled- SWAP) gate. This is a gate where two qubits are swapped depending on the value of the third.
Usually the Fredkin gate requires implementing a circuit of five logic operations. The research team used the quantum entanglement of photons -- particles of light -- to implement the controlled-SWAP operation directly.
"There are quantum computing algorithms, such as Shor's algorithm for factorising prime numbers, that require the controlled-SWAP operation.
Professor Geoff Pryde, from Griffith's Centre for Quantum Dynamics, is the project's chief investigator.
A report published in Christian Science Monitor said, "Scientists, governments, and large corporations seek powerful computers for a number of activities from modeling air traffic control and molecular compositions to predicting weather events and cracking passwords. The more complex the operation and the more independent variables need to be simulated, the more processing power is required. A quantum computer would be able to solve in one second a problem that could stump a traditional computer for 10,000 years, according to Hartmut Neven, director of engineering at Google"