Lattice Dynamics of Laser Excited Ferroelectric BaTiO₃

Abstract

We investigated the lattice dynamics of the prototypic ferroelectric barium titanate close to its ferroelectric--paraelectric phase transition aiming at a better understanding of the atomistic nature of the transition. The usage of time-resolved X-ray techniques allows to disentangle lattice motion and unit cell changes, which, in part, relate to the ferroelectric polarization. In the quasi-static case both the electrical and the laser excitation show a mean-field, simple thermal behaviour, while for time scales shorter than nanoseconds the impulsive nature of the excitation becomes visible.

Probing Ultrafast Dynamics of Ferroelectrics by Time‐Resolved Pump‐Probe Spectroscopy

“…The pump-probe techniques even give rise to an additional degree of freedom, and in turn provide potential approaches to nondestructive readout in nonvolatile ferroelectric memory. The pump-probe techniques are being developed for higher temporal resolution, higher [ 42,52,72,86,88] BSTO, [ 89,90] BTO, [38] THz emission spectroscopy 𝛼-(ET) 2 I 3 , [73] TPOP TTF-CA, [51,92] LNO, [37] TPXP croconic acid, [93] OPSP THz pump SHG probe OPXP Lattice dynamics lattice vibration/ optical phonon excitation, acoustic phonon, acousto-optic conversion, ultrafast photoinduced strain, phase transition, photovoltaic response, electron-lattice coupling, electron-phonon coupling, phonon-polariton coupling, lattice-polarization coupling THz time domain spectroscopy BTO, [95,112] PZT, [ 102,103] STO, [ 40,43,68,113,114] BFO [ 53,71,82,100,101,104] OPOP LNO, [55,101] PTO, [ 94,96,115] TTF-CA, [41] Sn 2 P 2 S 6 [97] OPSP THz pump SHG probe OPXP TPOP THz emission spectroscopy Spin dynamics magnetic/spin excitation, electric-magnetic coupling, magnon-phonon coupling, electromagnon OPOP BFO, [ 81,83,105,107,108] BSTO/LCMO,…”

Structural and Thermal Characterisation of Nanofilms by Time-Resolved X-ray Scattering

“…A simpler approach may meanwhile be accessible on any synchrotron beamline, taking advantage of developments in detector technology [65] and data processing. With avalanche photo-detectors a time resolution on the nanosecond scale can be achieved [66,67]. This would allow recording shifts in powder peak position of the gold layer without a dedicated pump-probe beamline.…”

Designing Ultrafast Cooling Rate for Room Temperature Electrocaloric Effects by Phase‐Field Simulations

“…Benefit from the rapid development and application of terahertz frequency technology, [8,9] it is possible to detect electrons, phonons, and spin dynamics on picosecond to nanosecond time scales and submicron length scales. [10][11][12][13][14] Recently, the dynamic process of ferroelectrics has attracted intensive research interest, and many efforts have been made to track their ultrafast dynamic behavior in real-time. [15][16][17][18][19][20][21] Experimentally, research on the ultrafast dynamics of ferroelectrics has mainly focused on ultrafast polarization dynamics and modulation, [22,23] photopolarization, and mechanics, [24,25] phase transition, [26] electronphonon/phonon-polariton/electric-magnetic coupling, [27,28] carrier dynamics and radiative recombination.…”