Attosecond Pulse (IMAGE) Optica Caption This is a spatial profile of an attosecond pulse train generated by a usual laser femtosecond laser beam. Credit Fabien Quéré, the French Commissariat à l'Energie Atomique Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.