Washington: Physicists have developed a new atomic clock that surpasses previous records for accuracy of current US time standard, making it the world's most accurate atomic clock. Developed by physicists at JILA, a joint institute of the Commerce Department's National Institute of Standards and Technology (NIST) and the University of Colorado at Boulder, the new clock is based on thousands of strontium atoms trapped in grids of laser light. In the JILA clock, a few thousand atoms of the alkalineearth metal strontium are held in a column of about 100 pancake-shaped traps called an "optical lattice'. The lattice is formed by standing waves of intense near-infrared laser light. Forming a sort of artificial crystal of light, the lattice constrains atom motion and reduces systematic errors that occur in clocks that use moving balls of atoms. Using thousands of atoms at once also produces stronger signals and eventually may yield more precise results than clocks relying on a single ion, such as mercury. This experimental strontium clock is in fact now the world's most accurate atomic clock based on neutral atoms, more than twice as accurate as the NIST-F1 standard cesium clock in Boulder. ANI