decoherence tagged posts

Researchers from RIKEN and QuTech — a collaboration between TU Delft and the Netherlands Organisation for Applied Scientific Research (TNO) — have achieved a key milestone toward the development of a fault-tolerant quantum computer. They were able to demonstrate a two-qubit gate fidelity of 99.5 percent — higher than the 99 percent considered to be the threshold for building fault-tolerant computers — using electron spin qubits in silicon, which are promising for large-scale quantum computers as the nanofabrication technology for building them already exists. This study was published in Nature.

The world is currently in a race to develop large-scale quantum computers that could vastly outperform classical computers in certain area...

Fast-forwarding quantum calculations skips past the time limits imposed by decoherence, which plagues today’s machines. A new algorithm that fastforwards simulations could bring greater use ability to current and near-term quantum computers, opening the way for applications to run past strict time limits that hamper many quantum calculations.

“Quantum computers have a limited time to perform calculations before their useful quantum nature, which we call coherence, breaks down,” said Andrew Sornborger of the Computer, Computational, and Statistical Sciences division at Los Alamos National Laboratory, and senior author on a paper announcing the research...

Jonathan G. Richens, John H. Selby, and Sabri W. Al-Safi. “Entanglement is Necessary for Emergent Classicality in All Physical Theories.” Physical Review Letters. DOI: 10.1103/PhysRevLett.119.080503

Is entanglement really necessary for describing the physical world, or is it possible to have some post-quantum theory without entanglement? In a new study, physicists have mathematically proved that any theory that has a classical limit-meaning that it can describe our observations of the classical world by recovering classical theory under certain conditions-must contain entanglement...

Trapped Ytterbium ions were used as one of the most advanced laboratory quantum systems for this study. Professor Biercuk’s research laboratories are now located in the Sydney Nanoscience Hub, after six years as a visiting scientist at the National Measurement Institute.
Credit: University of Sydney

What if big data could help you see the future and prevent your mobile phone from breaking before it happened? Scientists at the University of Sydney have demonstrated the ability to “see” the future of quantum systems, and used that knowledge to preempt their demise, in a major achievement that could help bring the strange and powerful world of quantum technology closer to reality...