Wednesday, November 24, 2004
Quantum chip circuitry demonstrated
EE Times - Quantum chip circuitry demonstrated: "Yale University researchers have demonstrated how to build a quantum computer operating on quantum bits, or qubits, which hold a superposition of quantum states. [...] The advantages of Yale's method include the relatively small size of its qubit repositories - about a square micron - and the ability to read a qubit's state without disturbing it - the bane of quantum computers to date. [...] The Yale approach stored qubits in a Cooper-box with over 1 billion superconducting aluminum atoms acting together, thereby providing a kind of quantum momentum that allowed a 'probing' photon to read out a qubit's state from the Cooper-box without changing its state."
Updates: I found this pdf to be a pretty good lightly-technical explanation of the experiment. Also, here [zhurnal.net] and here [www.lkb.ens.fr] are some interesting explanations of Quantum Non-Demolition.
The NSA Wants Your Quantum Algorithms
NSA Funding Opportunity in Quantum Computing Algorithms: "The National Security Agency solicits proposals for one-year research grants in the area of Quantum Computing Algorithms. [...] We are not interested in funding work such as quantum error correction, which supports the 'infrastructure' of quantum computation but is not a quantum algorithm in our sense. We are more interested in algorithms related to number theory, algebra, and combinatorics than in topics such as physical modeling and database analysis."
Sunday, November 14, 2004
Single Field Qubit Control
Single field shapes quantum bits TRN 110304: "Researchers have recently realized that it may be possible to control the electrons in a quantum computer using a single magnetic field rather than having to produce extremely small, precisely focused magnetic fields for each electron"
Grover's Sampling Algorithm
Quantum Sampling Algorithm TRN 062800: "The sampling algorithm, written by Bell Labs' researcher Lov K. Grover, enables three types of applications for quantum computing: statistical sampling, searching with sketchy information and Monte Carlo integration [...] Although the sampling algorithm is probably not as 'novel and exciting' as Grover's original search algorithm, no one doubts the importance of sampling on quantum computers"
Update: Sorry for not noticing sooner, but this story is fairly old (July 2000) which I should have at least mentioned.
Saturday, November 06, 2004
Particle Physics for the Rest of Us
Symmetry Magazine has recently debuted, which is a joint venture of SLAC and Fermi Lab. The editor, David Harris, also has a blog.
Tuesday, November 02, 2004
August Wrap Up
-2 million correlated entangled photon pairs produced per second
-Entangled quantum dots
-New way to synthesize quantum dots (and more here)
-Photon teleportation over 600m
-Controlled emission rates of quantum dots
-Five photons entangled
-Open destination quantum teleportation