In collaboration with several research groups, a team of RTG researchers has successfully pushed the temporal resolution of lightwave-driven scanning tunneling microscopy into the attosecond regime. This allows them to reach the quantum-mechanical space-time limit in ultrafast real-space microscopy, for the first time. Upon excitation with single-cycle near-infrared waveforms, the electrons in the STM tip acquire energy which is accompanied by a loss of localization of the wavefunction – a process that can be directly imaged in the microscope. Yet with optimal settings, the newly developed microscope maintains atomic spatial resolution, enabling investigations of ultrafast electron dynamics with atomic-scale precision.
In the future, electron wave packets can be used to selectively trigger chemical reactions and to observe, on their natural length and time scales, how chemical bonds are broken and rearranged. In the long term, the insights gained could also contribute to driving electronic and quantum information devices at the intrinsic speed limit of electron motion itself.
The results were published in Nature photonics.
© Brad Baxley, PtW