31 January 2014 Capturing of fs pulses on the nanometer scale

Second harmonic nano-particles for fs pulse control.

Advances on Second Harmonic Nano-Particles for Pulse Control in Light: Science & Applications In a recent study carried out by Nicolò Accanto and colleagues in the Molecular NanoPhotonics group led by Niek van Hulst, they have used various types of non-linear nanoparticles to measure and control ultrashort (17 fs) pulses on the nanoscale, beyond the diffraction limit. The work was published in the new Nature family journal Light: Science & Applications .

Light-matter interactions at the nano-scale, using plasmonic nanoparticles, quantum dots and molecules are an active field of research with applications in biosensing, nano-imaging, light-harvesting, local heating, etc. The next challenge is to combine the nano-scale with ultrafast time control: ultrafast nano-photonics, for which both the spatial diffraction limit and temporal Fourier limit have to be met at the same time.

In this paper Nicolò Accanto and colleagues demonstrate that non-linear nanoparticles are an ideal platform to reach the limits both in space and time. Exploiting the second harmonic spectroscopy and broad band phase control they show that few fs laser pulses can be compressed and shaped in time with unprecedented spatial accuracy. The presented method is versatile and simple to implement; thus will ease investigation of nanometer - femtosecond phenomena, e.g. the ultrafast quantum effects in single quantum dots and molecules, the ultrafast dynamics of light-graphene interaction, the ultrafast response of plasmonic antennas, the energy transfer in photosynthetic and photovoltaic complexes, etc.