Tuesday, April 27, 2004
Programming Matter - Quantum Dots
Quantum Dots, from Computerworld: Programming Matter: "With programmable quantum dots, McCarthy says, you can create metal traces inside a solid object, create an electric circuit to perform a particular task and then erase it once it's complete."
IBM, Stanford Spintronics Partnership
From Newsfactor: IBM, Stanford Turn to Spintronics: "IBM and Stanford University are putting their heads together on a new microelectronics technology dubbed "spintronics" [...] Magnetic RAM (MRAM) is the next spintronic device in the works. It has the potential to be a non-volatile memory that runs circles around non-volatile Flash memory"
Saturday, April 17, 2004
Virtual Journal of Quantum Information--April 2004
Found here: Virtual Journal of Quantum Information--April 2004. The one and only algorithm article from this issue can also be found here: Quantum algorithms for phase space tomography [arxiv.org]
Sunday, April 11, 2004
From The Globe and Mail, a story about the Perimeter Institute in Waterloo, Ontario: "At present, the world's record is a device [...] that can generate seven qubits. This year, Dr. [Raymond] Laflamme [of the Perimeter Institute] is attempting to increase that to 10 [...]"
Friday, April 09, 2004
4 Qubit Search Implementation
Technology Review: Sturdy Quantum Computing Demoed: "Researchers at the University of Toronto have built a prototype quantum computer that can execute a quantum search algorithm despite environmental noise. The computer uses protected logical qubits that are made from multiple physical qubits. The prototype has just four qubits, but the method has the potential to someday be used in practical quantum computers, which require thousands or millions of qubits. [...] The work appeared in the November 21, 2003 issue of Physical Review Letters."
Saturday, April 03, 2004
Exploring the Classical/Quantum Boundary
In PhysicsWeb - Physicists move closer to the quantum limit: "To find out whether or not the uncertainty principle extends up to the macroscopic world, Schwab and colleagues studied the motion of a vibrating mechanical arm made from silicon nitride."
Friday, April 02, 2004
Combatting Decoherence, Plus Low Overhead Error Correction
The Economist.com has a story on Quantum computing. The first half is the standard intro, but some interesting new results are mentioned in the second half of the story:
"Chikako Uchiyama of Yamanashi University, in Japan, discussed how, in the general case, the application of very short pulses, poetically known as bang-bang pulses, at regular intervals can serve not only to suppress decoherence, but also to maintain entanglement—the quantum coupling between several qubits which allows computations to get done."
Also: "Kaveh Khodjasteh of the University of Toronto looked at a related question, focusing on decoherence rather than disentanglement. He showed how a quantum error-correcting code which introduced only one extra qubit for error correction would create a robust system for quantum computation which had tolerance for faults caused by spontaneous emission, another bizarre quantum effect."