Isolated attosecond pulses generated by relativistic effects in a wavelength-cubed focal volume

Lasers that provide an energy encompassed in a focal volume of a few cubic wavelengths (lambda3) can create relativistic intensity with maximal gradients using minimal energy. With particle-in-cell simulations we found that single 200-as pulses could be produced efficiently in a lambda3 laser pulse reflection by means of deflection and phase compression caused by the coherent motion of the plasma electrons that emit these pulses. This novel technique is efficient (approximately 10%) and can produce single attosecond pulses from the millijoule to the joule level.