Abstract
Due to the strong dependence of electronic properties on the local bonding environment, a full characterization of the structural dynamics in ultrafast experiments is critical. Here, we report the dynamics and structural refinement at nanosecond time scales of a perovskite thin film by combining optical excitation with time-resolved X-ray diffraction. This is achieved by monitoring the temporal response of both integer and half-integer diffraction peaks of LaVO3 in response to an above-band-gap 800 nm pump pulse. We find that the lattice expands by 0.1% out of plane, and the relaxation is characterized by a biexponential decay with 2 and 12 ns time scales. We analyze the relative intensity change in half-integer peaks and show that the distortions to the substructure are small: the oxygen octahedral rotation angles decrease by ∼0.3° and La displacements decrease by ∼0.2 pm, which directly corresponds to an ∼0.8° increase in the V-O-V bond-angles, an in-plane V-O bond length reduction of ∼0.3 pm, and an unchanged out-of-plane bond length. This demonstration of tracking the atomic positions in a pump-probe experiment provides experimentally accessible values for structural and electronic tunability in this class of materials and will stimulate future experiments.
| Original language | English (US) |
|---|---|
| Article number | 014502 |
| Journal | Structural Dynamics |
| Volume | 6 |
| Issue number | 1 |
| DOIs | |
| State | Published - Jan 1 2019 |
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All Science Journal Classification (ASJC) codes
- Radiation
- Instrumentation
- Condensed Matter Physics
- Spectroscopy
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Structural dynamics of LaVO3 on the nanosecond time scale. / Brahlek, Matthew; Stoica, Vladimir A.; Lapano, Jason; Zhang, Lei; Akamatsu, Hirofumi; Tung, I. Cheng; Gopalan, Venkatraman; Walko, Donald A.; Wen, Haidan; Freeland, John W.; Engel-Herbert, Roman.
In: Structural Dynamics, Vol. 6, No. 1, 014502, 01.01.2019.Research output: Contribution to journal › Article
TY - JOUR
T1 - Structural dynamics of LaVO3 on the nanosecond time scale
AU - Brahlek, Matthew
AU - Stoica, Vladimir A.
AU - Lapano, Jason
AU - Zhang, Lei
AU - Akamatsu, Hirofumi
AU - Tung, I. Cheng
AU - Gopalan, Venkatraman
AU - Walko, Donald A.
AU - Wen, Haidan
AU - Freeland, John W.
AU - Engel-Herbert, Roman
PY - 2019/1/1
Y1 - 2019/1/1
N2 - Due to the strong dependence of electronic properties on the local bonding environment, a full characterization of the structural dynamics in ultrafast experiments is critical. Here, we report the dynamics and structural refinement at nanosecond time scales of a perovskite thin film by combining optical excitation with time-resolved X-ray diffraction. This is achieved by monitoring the temporal response of both integer and half-integer diffraction peaks of LaVO3 in response to an above-band-gap 800 nm pump pulse. We find that the lattice expands by 0.1% out of plane, and the relaxation is characterized by a biexponential decay with 2 and 12 ns time scales. We analyze the relative intensity change in half-integer peaks and show that the distortions to the substructure are small: the oxygen octahedral rotation angles decrease by ∼0.3° and La displacements decrease by ∼0.2 pm, which directly corresponds to an ∼0.8° increase in the V-O-V bond-angles, an in-plane V-O bond length reduction of ∼0.3 pm, and an unchanged out-of-plane bond length. This demonstration of tracking the atomic positions in a pump-probe experiment provides experimentally accessible values for structural and electronic tunability in this class of materials and will stimulate future experiments.
AB - Due to the strong dependence of electronic properties on the local bonding environment, a full characterization of the structural dynamics in ultrafast experiments is critical. Here, we report the dynamics and structural refinement at nanosecond time scales of a perovskite thin film by combining optical excitation with time-resolved X-ray diffraction. This is achieved by monitoring the temporal response of both integer and half-integer diffraction peaks of LaVO3 in response to an above-band-gap 800 nm pump pulse. We find that the lattice expands by 0.1% out of plane, and the relaxation is characterized by a biexponential decay with 2 and 12 ns time scales. We analyze the relative intensity change in half-integer peaks and show that the distortions to the substructure are small: the oxygen octahedral rotation angles decrease by ∼0.3° and La displacements decrease by ∼0.2 pm, which directly corresponds to an ∼0.8° increase in the V-O-V bond-angles, an in-plane V-O bond length reduction of ∼0.3 pm, and an unchanged out-of-plane bond length. This demonstration of tracking the atomic positions in a pump-probe experiment provides experimentally accessible values for structural and electronic tunability in this class of materials and will stimulate future experiments.
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U2 - 10.1063/1.5045704
DO - 10.1063/1.5045704
M3 - Article
C2 - 30868087
AN - SCOPUS:85060131127
VL - 6
JO - Structural Dynamics
JF - Structural Dynamics
SN - 2329-7778
IS - 1
M1 - 014502
ER -