Unconventional slowing down of electronic recovery in photoexcited charge-ordered La1/3Sr2/3FeO3

Zhu, Yi; Hoffman, Jason; Rowland, Clare E.; Park, Hyowon; Walko, Donald A.; Freeland, John W.; Ryan, Philip J.; Schaller, Richard D.; Bhattacharya, Anand; Wen, Haidan

doi:10.1038/s41467-018-04199-4

Title: Unconventional slowing down of electronic recovery in photoexcited charge-ordered La_1/3Sr_2/3FeO₃

Journal Article · 04 May 2018 · Nature Communications

DOI: https://doi.org/10.1038/s41467-018-04199-4 · OSTI ID:1436464

Zhu, Yi ^[1]; Hoffman, Jason ^[1]; Rowland, Clare E. ^[2]; Park, Hyowon ^[3]; Walko, Donald A. ^[1];

^[1]; Ryan, Philip J. ^[4]; Schaller, Richard D. ^[2];

^[1]; Wen, Haidan ^[1]

Argonne National Lab. (ANL), Argonne, IL (United States)
Argonne National Lab. (ANL), Argonne, IL (United States); Northwestern Univ., Evanston, IL (United States)
Argonne National Lab. (ANL), Argonne, IL (United States); Univ. of Illinois at Chicago, Chicago, IL (United States)
Argonne National Lab. (ANL), Argonne, IL (United States); Dublin City Univ., Dublin (Ireland)

Ordered electronic phases are intimately related to emerging phenomena such as high Tc superconductivity and colossal magnetoresistance. The coupling of electronic charge with other degrees of freedom such as lattice and spin are of central interest in correlated systems. Their correlations have been intensively studied from femtosecond to picosecond time scales, while the dynamics of ordered electronic phases beyond nanoseconds are usually assumed to follow a trivia thermally driven recovery. Here, we report an unusual slowing down of electronic phases across a first-order phase transition, far beyond thermal relaxation time. Following optical excitation, the recovery time of both transient optical reflectivity and x-ray diffraction intensity from a charge-ordered superstructure in a La_1/3Sr_2/3FeO₃ thin film increases by orders of magnitude longer than the independently measured lattice cooling time when the sample temperature approaches the phase transition temperature. The combined experimental and theoretical investigations show that the slowing down of electronic recovery corresponds to the pseudo-critical dynamics that originates from magnetic interactions close to a weakly first-order phase transition. As a result, this extraordinary long electronic recovery time exemplifies an interplay of ordered electronic phases with magnetism beyond thermal processes in correlated systems.

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Research Organization:: Argonne National Laboratory (ANL), Argonne, IL (United States)

Sponsoring Organization:: USDOE Office of Science (SC), Basic Energy Sciences (BES)

Grant/Contract Number:: AC02-06CH11357

OSTI ID:: 1436464

Journal Information:: Nature Communications, Vol. 9, Issue 1; ISSN 2041-1723

Publisher:: Nature Publishing GroupCopyright Statement

Country of Publication:: United States

Language:: English

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Cited by: 12 works

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Title: Unconventional slowing down of electronic recovery in photoexcited charge-ordered La_1/3Sr_2/3FeO₃