Carrier Dynamics in a-Fe2O3 (0001) Thin Films and Single Crystals Probed by Femtosecond Transient Absorption and Reflectivity

Joly, Alan G; Williams, Josh R; Chambers, Scott A; Xiong, Gang; Hess, Wayne P; Laman, David M

doi:10.1063/1.2177426

Title: Carrier Dynamics in a-Fe2O3 (0001) Thin Films and Single Crystals Probed by Femtosecond Transient Absorption and Reflectivity

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Abstract

Femtosecond transient reflectivity and absorption is used to measure the carrier lifetimes in α-Fe2O3 thin films and hematite single crystals. The results from the thin films show that initially excited hot electrons relax to the bandedge within 300 femtoseconds and then recombine with holes or trap within 5 pioseconds. The trapped electrons have a lifetime of hundreds of picoseconds. The trapped electrons have a lifetime of hundreds of picoseconds. Transient reflectivity measurements from hematite (α-Fe2O3) single crystals show similar but slightly faster dynamics. In hematite, the transient reflectivity displays oscillations due to the formation of longitudinal acoustic phonons generated following absorption of the ultrashort excitation pulse.

Authors:: Joly, Alan G; Williams, Josh R; Chambers, Scott A; Xiong, Gang; Hess, Wayne P; Laman, David M

Publication Date:: Wed Mar 01 00:00:00 EST 2006

Research Org.:: Pacific Northwest National Lab. (PNNL), Richland, WA (United States). Environmental Molecular Sciences Lab. (EMSL)

Sponsoring Org.:: USDOE

OSTI Identifier:: 882953

Report Number(s):: PNNL-SA-45700
11105; KC0302010

DOE Contract Number:: AC05-76RL01830

Resource Type:: Journal Article

Journal Name:: Journal of Applied Physics, 99(5):Article: 053521 (6 pages)

Additional Journal Information:: Journal Name: Journal of Applied Physics, 99(5):Article: 053521 (6 pages)

Country of Publication:: United States

Language:: English

Subject:: Environmental Molecular Sciences Laboratory

Citation Formats


                    Joly, Alan G, Williams, Josh R, Chambers, Scott A, Xiong, Gang, Hess, Wayne P, and Laman, David M. Carrier Dynamics in a-Fe2O3 (0001) Thin Films and Single Crystals Probed by Femtosecond Transient Absorption and Reflectivity.  United States: N. p., 2006. 
        Web.  doi:10.1063/1.2177426.

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                    Joly, Alan G, Williams, Josh R, Chambers, Scott A, Xiong, Gang, Hess, Wayne P, & Laman, David M. Carrier Dynamics in a-Fe2O3 (0001) Thin Films and Single Crystals Probed by Femtosecond Transient Absorption and Reflectivity.  United States.  https://doi.org/10.1063/1.2177426

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                    Joly, Alan G, Williams, Josh R, Chambers, Scott A, Xiong, Gang, Hess, Wayne P, and Laman, David M. 2006.  
        "Carrier Dynamics in a-Fe2O3 (0001) Thin Films and Single Crystals Probed by Femtosecond Transient Absorption and Reflectivity".  United States.  https://doi.org/10.1063/1.2177426.

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@article{osti_882953,

  title        = {Carrier Dynamics in a-Fe2O3 (0001) Thin Films and Single Crystals Probed by Femtosecond Transient Absorption and Reflectivity},

  author       = {Joly, Alan G and Williams, Josh R and Chambers, Scott A and Xiong, Gang and Hess, Wayne P and Laman, David M},

  abstractNote = {Femtosecond transient reflectivity and absorption is used to measure the carrier lifetimes in α-Fe2O3 thin films and hematite single crystals. The results from the thin films show that initially excited hot electrons relax to the bandedge within 300 femtoseconds and then recombine with holes or trap within 5 pioseconds. The trapped electrons have a lifetime of hundreds of picoseconds. The trapped electrons have a lifetime of hundreds of picoseconds. Transient reflectivity measurements from hematite (α-Fe2O3) single crystals show similar but slightly faster dynamics. In hematite, the transient reflectivity displays oscillations due to the formation of longitudinal acoustic phonons generated following absorption of the ultrashort excitation pulse.},

  doi          = {10.1063/1.2177426},

  url          = {https://www.osti.gov/biblio/882953},
  journal      = {Journal of Applied Physics, 99(5):Article: 053521 (6 pages)},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {Wed Mar 01 00:00:00 EST 2006},

  month        = {Wed Mar 01 00:00:00 EST 2006}

}

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