Quantum Frontiers lecture: Dr. David Wineland on Atomic Clocks and Ion Trap Quantum Computing

Описание: Prof. David Wineland speaks about atomic clocks and ion-trap quantum computers at the Quantum Frontiers Distinguished Lecture, presented by the Institute for Quantum Computing and the University of Waterloo's Department of Physics and Astronomy.

Wineland is a Fellow of the National Institute of Standards and Technology and group leader of the Ion Storage group in the Time and Frequency Division at NIST Boulder, CO.

Atoms absorb electromagnetic radiation at certain precise frequencies. Knowing this, a recipe for making an atomic clock is fairly simple to state: we first need an oscillator to produce radiation and a device that tells us when the atoms absorb it, thereby indicating that the oscillator frequency is synchronized with the atoms' absorption frequency. To make a clock from this apparatus, we then simply count cycles of the oscillator -- the duration of a certain number of cycles defines a unit of time, for example, the second. In one of the world's most accurate clocks, we count the cycles of an oscillator that has a frequency of 1,052,871,833,148,990.44 cycles per second -- corresponding to a near-ultraviolet absorption frequency in 27Al+ ions. At this level of precision, many effects, including those due to special and general relativity, can affect our measurements; therefore, our primary task is to determine and correct for these perturbing effects. For many centuries and still continuing today, a primary application of accurate clocks is for precise navigation.