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Terahertz Pulses Reveal Ultrafast Lattice Dynamics of Stripes

Illustration of laser pulse impinging on stripe-phase LSNO. Inset: transient THz conductivity of the Ni-O bending mode.

Scientific Achievement
Ultrashort terahertz pulses track the crystal distortions during melting of stripes in a correlated oxide, exposing time-delayed interactions underlying atomic-scale patterns.

Significance and Impact
Reveals dynamic "glue" of electronic & vibrational stripe components, relevant to understanding dynamics of symmetry-broken phases in complex energy materials (e.g. high-TC superconductors).

Research Details

  • Electronic stripe order in the nickelate La1.75Sr0.25NiO4 is quenched via ultrafast optical excitation.
  • THz pulses probe the Ni-O bending mode: side peaks are a fingerprint of stripe-periodic lattice distortions.
  • Charges are delocalized immediately, while the crystal symmetry exhibits multi-scale melting over 0.4–1.5 ps.

G Coslovich, AF Kemper, S Behl, B Huber, HA Bechtel, T Sasagawa, MC Martin, A Lanzara, and RA Kaindl, Science Advances 3, 1600735 (2017)