High-order harmonic generation from atoms ionized by femtosecond laser pulses has been a promising approach for the development of coherent short-wavelength sources. However, the realization of a ...

High-order harmonic upconversion of femtosecond lasers produces a unique source of short-wavelength light with femtosecond-to-attosecond pulse duration. However, because the involved nonlinear medium ...

Nudge something away from where it was at rest, and often it will push back. And then overshoot. From atoms to bridges to wheeled luggage, much of the world is in simple harmonic motion Yesterday my ...