Synopsis: Attoseconds for all

An advance in attosecond pulse generation will make it easier to produce a single pulse.
Synopsis figure
Illustration: X. Feng et al., Phys. Rev. Lett. (2009)

Attosecond physics is a burgeoning field in which researchers use ultrashort optical pulses to excite atoms and molecules and follow the electron dynamics. Driving atoms with longer-duration pulse sequences can generate trains of attosecond pulses, but what workers in this field really need are isolated attosecond pulses. However, the technologies for slicing out single pulses can be complex and difficult to implement. Now, Ximao Feng and colleagues at Kansas State University, US, report in Physical Review Letters a relatively straightforward procedure for producing single pulses as short as 148 attoseconds.

Existing methods to pick a single pulse from a pulse train, a technique called “gating,” rely on controlling the light’s amplitude or polarization. Feng et al. have improved upon previous efforts in which two-color gating (interference of the driving laser frequency plus its second harmonic) and polarization gating (two counterrotating circularly polarized pulses that only drive attosecond pulse generation when they form a linear polarization) create a single pulse. The downside of these methods was that they put stringent limits on how long the driving pulses could be. By using elliptically polarized pulses, Feng et al. have been able to relax the requirements so that longer driving pulses, which are much easier to create in the lab, can be used. Moreover, the generated ultrashort pulses can have much higher energies, placing them in the realm of strongly nonlinear attosecond physics. – David Voss


More Features »


More Announcements »

Subject Areas


Previous Synopsis

Atomic and Molecular Physics

An ultracold graphene analog

Read More »

Next Synopsis

Materials Science

Predicting crystal structures

Read More »

Related Articles

Synopsis: Getting Plasma in a Twist

Synopsis: Getting Plasma in a Twist

Laser vortex beams can exchange their optical angular momentum with a plasma from which they are reflected. Read More »

Synopsis: Starting Fluid for Laser Fusion
Energy Research

Synopsis: Starting Fluid for Laser Fusion

A laser-based fusion experiment demonstrates that liquid fuel capsules could rectify problems encountered with ice-based fuel capsules. Read More »

Synopsis: Graphene’s Elegant Optics Explained

Synopsis: Graphene’s Elegant Optics Explained

Theoretical calculations anchor graphene’s simple optical absorption in its two-dimensional structure instead of its cone-shaped energy bands. Read More »

More Articles