A singlemode optical fiber designed to reduce chromatic dispersion. The fiber core is fabricated in several layers with different refractive indices running in parallel throughout its length.

Dispersion is a fundamental measure of risk and opportunity in the stock market; it measures how differently stocks are performing, or are expected to perform. The Dispersion Index was launched in ...

Roula Khalaf, Editor of the FT, selects her favourite stories in this weekly newsletter. The average hedge fund manager across all strategies has returned just less than 7 per cent so far this year, ...