Ultrafast light-induced shear strain probed by time-resolved x-ray diffraction: Multiferroic 
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mi>BiFeO</mml:mi><mml:mn>3</mml:mn></mml:msub></mml:math>
 as a case study

Juvé, Vincent; Gu, Ruizhe; Gable, S.; Maroutian, Thomas; Vaudel, G.; Matzen, Sylvia; Chigarev, Nikolay; Raetz, Samuel; Gusev, Vitalyi; Viret, M.; Jarnac, Amélie; Laulhé, Claire; Maznev, A. A.; Dkhil, Brahim; Ruello, P.

doi:10.1103/physrevb.102.220303

Cited by 10 publications

(17 citation statements)

References 45 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In our experiment, the light pulse impinges at normal incidence with a pump photon energy of 3 eV, which is larger than the BiFeO 3 bandgap (see Methods) ( 31 ). The absorption of a light pulse leads inevitably to the excitation of a strain pulse ( 32 , 33 ) that propagates through the film perpendicular to its surface ( 11 ). The crystal symmetry of the BiFeO 3 film (point-group m ) allows for the generation of both longitudinal and transverse acoustic waves, i.e., out-of-plane and in-plane atomic motions, respectively.…”

Section: Results and Analysismentioning

confidence: 99%

“…In a first step, we probe the change of the optical reflectivity in a pump-probe measurements with picosecond resolution. This allows us to reveal the different photo-induced acoustic modes through time-domain Brillouin light scattering ( 11 , 18 , 19 , 34 ) (see Methods). The black curve in Fig.…”

Section: Results and Analysismentioning

confidence: 99%

“…Hence, the photoexcitation cannot lead to in-plane atomic displacements along b m due to symmetry principles (see note S4). In other words, the photo-induced stress must have two components ( 11 , 18 , 33 , 43 ): an out-of-plane and in-plane components. These two stress components cause then atoms to move simultaneously along out-of-plane and in-plane directions ( 11 , 18 , 33 , 43 ).…”

Section: Results and Analysismentioning

confidence: 99%

See 2 more Smart Citations

Temporal and spatial tracking of ultrafast light-induced strain and polarization modulation in a ferroelectric thin film

Gu,

Juvé,

Laulhé

et al. 2023

Sci. Adv.

Self Cite

View full text Add to dashboard Cite

Ultrashort light pulses induce rapid deformations of crystalline lattices. In ferroelectrics, lattice deformations couple directly to the polarization, which opens the perspective to modulate the electric polarization on an ultrafast time scale. Here, we report on the temporal and spatial tracking of strain and polar modulation in a single-domain BiFeO 3 thin film by ultrashort light pulses. To map the light-induced deformation of the BiFeO 3 unit cell, we perform time-resolved optical reflectivity and time-resolved x-ray diffraction. We show that an optical femtosecond laser pulse generates not only longitudinal but also shear strains. The longitudinal strain peaks at a large amplitude of 0.6%. The access of both the longitudinal and shear strains enables to quantitatively reconstruct the ultrafast deformation of the unit cell and to infer the corresponding reorientation of the ferroelectric polarization direction in space and time. Our findings open new perspectives for ultrafast manipulation of strain-coupled ferroic orders.

show abstract

Section: Results and Analysismentioning

confidence: 99%

Section: Results and Analysismentioning

confidence: 99%

Section: Results and Analysismentioning

confidence: 99%

See 1 more Smart Citation

Temporal and spatial tracking of ultrafast light-induced strain and polarization modulation in a ferroelectric thin film

Gu,

Juvé,

Laulhé

et al. 2023

Sci. Adv.

Self Cite

View full text Add to dashboard Cite

show abstract

“…Already this technologically simple approach has many more applications beyond the current manuscript. Moreover, PUX can be extended to asymmetric diffraction geometries that are sensitive to in-plane strain and to shear waves [133]. Optical phonons, i.e., coherent atomic motions within the crystallographic unit cell, are accessible via the modulations of the x-ray intensity through the structure factor [134][135][136].…”

Section: Discussionmentioning

confidence: 99%

“…A quantitative analysis of the three-dimensional strain response as discussed in Section 4.2 requires access to asymmetric Bragg reflections. This is also true for the detection of shear waves via PUX [26,133]. More details on the theory of x-ray diffraction can be found in dedicated books [147][148][149], and treatises that specialize on x-ray diffraction from thin films [150,151] or time-resolved x-ray diffraction [54,152,153].…”

Section: Discussionmentioning

confidence: 99%

Concepts and use cases for picosecond ultrasonics with x-rays

Mattern¹,

Reppert²,

Zeuschner³

et al. 2023

Preprint

View full text Add to dashboard Cite

We discuss picosecond ultrasonics experiments that complement the established, versatile all-optical schemes by utilizing ultrashort hard x-ray probe pulses. We focus on the extraction of the transient strain response from Bragg peak shifts in the symmetric diffraction condition for layered, nanoscopic structures upon excitation of metallic transducers with femtosecond laser pulses. This type of experiment yields direct, layer-specific and quantitative information on the shape and amplitude of picosecond strain pulses and quasi-static strain even for structures thinner than the optical skin depth. We revisit the inhomogeneous elastic wave equation, which is established for modeling the picosecond strain response and express the driving stress using Grüneisen parameters. This elucidates that the laser-induced stress is proportional to the thermal energy densities in the microscopic subsystems of the solid, i.e., electrons, phonons and spins. The strain response may therefore serve as an ultrafast quantitative proxy for the local energy-density and temperature rise. We underline the importance of the Poisson effect for the quantitative interpretation of the ultrafast strain response. The homogeneous laser-excitation of continuous thin films constrains their ultrafast in-plane expansion, thus suppressing the associated out-of-plane Poisson stress. However, it is present in near equilibrium heating experiments calibrating thermal expansion coefficients which requires an individual treatment of the ultrafast expansion. The selected experimental use cases encompass opaque as well as ultrathin metal-heterostructures, nanostructures and negative thermal expansion materials, that each pose a challenge to all-optical approaches.

show abstract