Scalable high-repetition-rate sub-half-cycle terahertz pulses from spatially indirect interband transitions.

ABSTRACT: Intense phase-locked terahertz (THz) pulses are the bedrock of THz lightwave electronics, where the carrier field creates a transient bias to control electrons on sub-cycle time scales. Key applications such as THz scanning tunnelling microscopy or electronic devices operating at optical clock rates call for ultimately short, almost unipolar waveforms, at megahertz (MHz) repetition rates. Here, we present a flexible and scalable scheme for the generation of strong phase-locked THz pulses based on shift currents in type-II-aligned epitaxial semiconductor heterostructures. The measured THz waveforms exhibit only 0.45 optical cycles at their centre frequency within the full width at half maximum of the intensity envelope, peak fields above 1.1 kV cm^-1 and spectral components up to

SUBMITTER: Meineke C 

PROVIDER: S-EPMC9127092 | biostudies-literature | 2022 May

REPOSITORIES: biostudies-literature