Exciton complexes in low dimensional transition metal dichalcogenides

doi:10.1063/1.4892488

Title: Exciton complexes in low dimensional transition metal dichalcogenides

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Abstract

We examine the excitonic properties of layered configurations of low dimensional transition metal dichalcogenides (LTMDCs) using the fractional dimensional space approach. The binding energies of the exciton, trion, and biexciton in LTMDCs of varying layers are analyzed, and linked to the dimensionality parameter α, which provides insight into critical electro-optical properties (relative oscillator strength, absorption spectrum, exciton-exciton interaction) of the material systems. The usefulness of α is highlighted by its independence of the physical mechanisms underlying the confinement effects of geometrical structures. Our estimates of the binding energies of exciton complexes for the monolayer configuration of transition metal dichalcogenides suggest a non-collinear structure for the trion and a positronium-molecule-like square structure for the biexciton.

Authors:

Thilagam, A., E-mail: thilaphys@gmail.com ^[1]

Information Technology, Engineering and Environment, University of South Australia, Adelaide 5095 (Australia)

Publication Date:: Thu Aug 07 00:00:00 EDT 2014

OSTI Identifier:: 22314547

Resource Type:: Journal Article

Journal Name:: Journal of Applied Physics

Additional Journal Information:: Journal Volume: 116; Journal Issue: 5; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0021-8979

Country of Publication:: United States

Language:: English

Subject:: 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ABSORPTION SPECTRA; BINDING ENERGY; CONFIGURATION; CONFINEMENT; LAYERS; MOLECULES; OPTICAL PROPERTIES; OSCILLATOR STRENGTHS; POSITRONIUM; TRANSITION ELEMENTS

Citation Formats


                    Thilagam, A., E-mail: thilaphys@gmail.com. Exciton complexes in low dimensional transition metal dichalcogenides.  United States: N. p., 2014. 
        Web.  doi:10.1063/1.4892488.

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                    Thilagam, A., E-mail: thilaphys@gmail.com. Exciton complexes in low dimensional transition metal dichalcogenides.  United States.  https://doi.org/10.1063/1.4892488

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                    Thilagam, A., E-mail: thilaphys@gmail.com. 2014.  
        "Exciton complexes in low dimensional transition metal dichalcogenides".  United States.  https://doi.org/10.1063/1.4892488.

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@article{osti_22314547,

  title        = {Exciton complexes in low dimensional transition metal dichalcogenides},

  author       = {Thilagam, A., E-mail: thilaphys@gmail.com},

  abstractNote = {We examine the excitonic properties of layered configurations of low dimensional transition metal dichalcogenides (LTMDCs) using the fractional dimensional space approach. The binding energies of the exciton, trion, and biexciton in LTMDCs of varying layers are analyzed, and linked to the dimensionality parameter α, which provides insight into critical electro-optical properties (relative oscillator strength, absorption spectrum, exciton-exciton interaction) of the material systems. The usefulness of α is highlighted by its independence of the physical mechanisms underlying the confinement effects of geometrical structures. Our estimates of the binding energies of exciton complexes for the monolayer configuration of transition metal dichalcogenides suggest a non-collinear structure for the trion and a positronium-molecule-like square structure for the biexciton.},

  doi          = {10.1063/1.4892488},

  url          = {https://www.osti.gov/biblio/22314547},
  journal      = {Journal of Applied Physics},

  issn         = {0021-8979},

  number       = 5,

  volume       = 116,

  place        = {United States},

  year         = {Thu Aug 07 00:00:00 EDT 2014},

  month        = {Thu Aug 07 00:00:00 EDT 2014}

}

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