Vacancy related defects in La{sub 0.5}Sr{sub 0.5}CoO{sub 3-{delta}} thin films

Title: Vacancy related defects in La{sub 0.5}Sr{sub 0.5}CoO{sub 3-{delta}} thin films

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Abstract

Laser ablated La{sub 0.5}Sr{sub 0.5}CoO{sub 3-{delta}} thin films have been studied by Doppler-broadening-detected positron annihilation using a variable-energy positron beam. The oxygen partial pressure during cooling from the growth temperature was altered through the range 760 torr to 10{sup -5} torr to change the oxygen non-stoichiometry of the films. The measured Doppler broadened lineshape parameter S was found to increase with increasing oxygen nonstoichiometry. For films cooled with an oxygen partial pressure of {le} 10{sup -4} Torr positron trapping to monovacancy type defects is inferred. For the film cooled in 10{sup -5} torr oxygen the magnitude of the increase in S, with respect to that measured from the film cooled in 760 Torr oxygen, showed positron trapping to vacancy cluster defects was occurring.

Authors:

Keeble, D J ^[1]; Krishnan, A ^[2]; Nielsen, B ^[3]

Univ. of Dundee (United Kingdom). Carnegie Lab. of Physics
Michigan Technological Univ., Houghton, MI (United States). Dept. of Physics
Brookhaven National Lab., Upton, NY (United States); and others

Publication Date:: 1996-12-31

Research Org.:: Brookhaven National Lab., Upton, NY (United States)

Sponsoring Org.:: USDOE Office of Energy Research, Washington, DC (United States)

OSTI Identifier:: 475599

Report Number(s):: BNL-64278; CONF-961202-109
ON: DE97006100; TRN: 97:003277

DOE Contract Number:: AA03-78CH00017

Resource Type:: Conference

Resource Relation:: Conference: 1996 Fall meeting of the Materials Research Society (MRS), Boston, MA (United States), 2-6 Dec 1996; Other Information: PBD: 1996

Country of Publication:: United States

Language:: English

Subject:: 36 MATERIALS SCIENCE; LANTHANUM OXIDES; VACANCIES; STRONTIUM OXIDES; COBALT OXIDES; DOPPLER BROADENING; THIN FILMS; PEROVSKITES

Citation Formats


                    Keeble, D J, Krishnan, A, and Nielsen, B. Vacancy related defects in La{sub 0.5}Sr{sub 0.5}CoO{sub 3-{delta}} thin films.  United States: N. p., 1996. 
        Web.

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                    Keeble, D J, Krishnan, A, & Nielsen, B. Vacancy related defects in La{sub 0.5}Sr{sub 0.5}CoO{sub 3-{delta}} thin films.  United States.

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                    Keeble, D J, Krishnan, A, and Nielsen, B. Tue .  
        "Vacancy related defects in La{sub 0.5}Sr{sub 0.5}CoO{sub 3-{delta}} thin films".  United States.  https://www.osti.gov/servlets/purl/475599.

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@article{osti_475599,

  title        = {Vacancy related defects in La{sub 0.5}Sr{sub 0.5}CoO{sub 3-{delta}} thin films},

  author       = {Keeble, D J and Krishnan, A and Nielsen, B},

  abstractNote = {Laser ablated La{sub 0.5}Sr{sub 0.5}CoO{sub 3-{delta}} thin films have been studied by Doppler-broadening-detected positron annihilation using a variable-energy positron beam. The oxygen partial pressure during cooling from the growth temperature was altered through the range 760 torr to 10{sup -5} torr to change the oxygen non-stoichiometry of the films. The measured Doppler broadened lineshape parameter S was found to increase with increasing oxygen nonstoichiometry. For films cooled with an oxygen partial pressure of {le} 10{sup -4} Torr positron trapping to monovacancy type defects is inferred. For the film cooled in 10{sup -5} torr oxygen the magnitude of the increase in S, with respect to that measured from the film cooled in 760 Torr oxygen, showed positron trapping to vacancy cluster defects was occurring.},

  doi          = {},

  url          = {https://www.osti.gov/biblio/475599},
  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {1996},

  month        = {12}

}

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