Nano Research

, Volume 6, Issue 3, pp 191–199 | Cite as

Fast and reliable identification of atomically thin layers of TaSe2 crystals

  • Andres Castellanos-Gomez
  • Efrén Navarro-Moratalla
  • Guillermo Mokry
  • Jorge Quereda
  • Elena Pinilla-Cienfuegos
  • Nicolás Agraït
  • Herre S. J. van der Zant
  • Eugenio Coronado
  • Gary A. Steele
  • Gabino Rubio-Bollinger
Research Article


Deposition of clean and defect-free atomically thin two-dimensional crystalline flakes on surfaces by mechanical exfoliation of layered bulk materials has proven to be a powerful technique, but it requires a fast, reliable and non-destructive way to identify the atomically thin flakes among a crowd of thick flakes. In this work, we provide general guidelines to identify ultrathin flakes of TaSe2 by means of optical microscopy and Raman spectroscopy. Additionally, we determine the optimal substrates to facilitate the optical identification of atomically thin TaSe2 crystals. Experimental realization and isolation of ultrathin layers of TaSe2 enables future studies on the role of the dimensionality in interesting phenomena such as superconductivity and charge density waves.

Graphical abstract


atomically thin layer metal dichalcogenide layered superconductor TaSe2 optical microscopy Raman spectroscopy 

Supplementary material

12274_2013_295_MOESM1_ESM.pdf (765 kb)
Supplementary material, approximately 776 KB.


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Copyright information

© Tsinghua University Press and Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  • Andres Castellanos-Gomez
    • 1
  • Efrén Navarro-Moratalla
    • 2
  • Guillermo Mokry
    • 3
  • Jorge Quereda
    • 3
  • Elena Pinilla-Cienfuegos
    • 2
  • Nicolás Agraït
    • 3
    • 4
  • Herre S. J. van der Zant
    • 1
  • Eugenio Coronado
    • 2
  • Gary A. Steele
    • 1
  • Gabino Rubio-Bollinger
    • 3
  1. 1.Kavli Institute of NanoscienceDelft University of TechnologyDelftThe Netherlands
  2. 2.Instituto Ciencia Molecular (ICMol)Univ. ValenciaPaternaSpain
  3. 3.Departamento de Física de la Materia Condensada (C-III)Universidad Autónoma de MadridMadridSpain
  4. 4.Instituto Madrileño de Estudios Avanzados en Nanociencia IMDEA-NanocienciaMadridSpain

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