English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

We investigate the ultrafast optical response of PbTe to an intensesingle-cycle terahertz pulse, resonant with the soft transverse optical (TO)phonon mode of the crystal. We detect multifrequency oscillations of thereflectance anisotropy, which we associate with nonlinear motion of the TOphonon oscillator excited directly by the terahertz pulse. Our observation ofmonotonically decaying optical anisotropy together with second harmonicoscillations of the TO mode is an evidence of a transient non-centrosymmetricstate of the crystal lattice that can be accompanied by the ferroelectricorder. We suppose that this state is induced in the PbTe crystal by the intenseterahertz pulse via alignment of the local polar nanodomains. This hypothesisis partially supported by the observation of coherent phonons near thesatellite phonon mode frequency that are impulsively generated by a femtosecondlaser pulse and are considerably enhanced by a synchronous terahertz pulse.

Anharmonic coherent dynamics of the soft phonon mode of a PbTe crystal