Ultrafast insulator-metal phase transition in VO 2 studied by multiterahertz spectroscopy
By A. Pashkin, C. Kübler, H. Ehrke, Ricardo Lopez, A. Halabica, Richard F Haglund, R. Huber, A. Leitenstorfer. 2011
185 citations recorded by the source corpus.
The ultrafast photoinduced insulator-metal transition in VO2 is studied at different temperatures and excitation fluences using multi-THz probe pulses. The spectrally resolved midinfrared response allows us to trace separately the dynamics of lattice and electronic degrees of freedom with a time resolution of 40 fs. The critical fluence of the optical pump pulse, which drives the system into a long-lived metallic state, is found to increase with decreasing temperature. Under all measurement conditions, we observe a modulation of the eigenfrequencies of the optical phonon modes induced by their anharmonic coupling to the coherent wave-packet motion of V-V dimers at 6.1 THz. Furthermore, we find a weak quadratic coupling of the electronic response to the coherent dimer oscillation resulting in a modulation of the electronic conductivity at twice the frequency of the wave-packet motion. The findings are discussed in the framework of a qualitative model based on an approximation of local photoexcitation of the vanadium dimers from the insulating state.
Subfields: Electrical and Electronic Engineering, Polymers and Plastics
View Paper: https://www.semanticscholar.org/paper/dd5b23fadc3d8c2b24602d6dff5707b0c02e0e16
How researchers see this paper
The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.
Citations in the corpus
- Ultrafast optical spectroscopy of strongly correlated materials and high-temperature superconductors: a non-equilibrium approach (2016, background): “and electron diffraction [476, 477], P-p spectroscopies in the THz/mid-IR/visible ranges [260, 271, 473, 478–481] and time-resolved photoemission spectroscopy [482].”