Optical Spectroscopy of 2 Dimensional Materials

Hyeonsik Cheong
Sogang University, Korea
16:45~17:30,November 19th, 2015

Abstract :

Optical spectroscopic tools are widely used to study the physical phenomena in various 2-dimensional materials. For example, Raman spectroscopy has been one of the most powerful tools in graphene research. It has been used to study the number of layers, stacking orders, carrier concentration, edge types, thermal conductivity, mechanical properties, electronic band structures, chemical modifications, and so on. In order to study the local properties on a microscopic scale, a confocal spectroscopy scheme is usually used. The measurement capabilities are expanded when the Raman spectrum is measured as a function of the excitation and/or the scattered polarizations. One may also study the effects on the Raman spectrum due to external perturbations such as an electrical field or strain, from which one can extract valuable information regarding the basic physics of graphene. Recently, the use of Raman spectroscopy is extended to the investigation of other layered two-dimensional (2D) layered materials, mainly for identification of the number of layers. For some luminescent 2D materials, photoluminescence is also used in combination with Raman spectroscopy. In this talk, recent progress in optical investigation of graphene and related 2D materials will be presented.



Research Interests :

  • Micro-Optical Investigation of Graphene and Related Materials
  • Optical Investigation of Semiconductor Nanostructures
  • Thin-film Oxides (Electrochromic WO3 and related oxides)
  • Development of Hydrogen Sensors
  • Optical Investigation of Biological Materials
  • Development of Biomedical Diagnostic Methods


Professional Activities:

  • 2015–Present President, Korean Graphene Society
  • 2012–Present Vice Chair, Division of Applied Physics, the Korean Physical Society
  • 2015–Present Editorial Board Member, Scientific Reports
  • 2013–2014 Director of Planning and External Relations, the Korean Physical Society
  • 2009–2010 Secretary, International Collaboration Committee, Korean Physical Society
  • 2005–2006 Director of Academic Activities, Korean Physical Society
  • 2003–2005 Editor, Journal of the Korean Physical Society
  • 2007–2009 Senior Vice President and President-elect, Korean Association of Foreign Student Advisors (KAFSA)
  • 2015 Conference Secretary, 9th International Conference on Advanced Materials and Devices (ICAMD 2015), Jeju, Korea, December 2015
  • 2013 Conference Secretary, 8th International Conference on Advanced Materials and Devices (ICAMD 2013), Jeju, Korea, December 2013
  • 2008–2011 Publication Vice Chair, 30th International Conference on Physics of Semiconductors (ICPS30), Seoul, Korea, July 2010
  • 2008–2009 Program Chair, 7th International Conference on Advanced Materials and Devices (ICAMD 2009), Jeju, Korea, December 2009
  • 2008–2009 Publication Chair, 8th International Meeting on Electrochromism (IME-8), Seoul, Korea, August 2008 and Guest Editor, Solar Energy Materials and Solar Cells
  • 2007–2009 Executive Editor, 10th Asia-Pacific Physics Conference (APPC10), Pohang, Korea, August 2007
  • 2006–2008 Member, International Advisory Committee, 29th International Conference on Physics of Semiconductors, Rio de Janeiro, Brazil, July 2008
  • 2003–2004 Deputy Secretary for Public Relations, the 34th International Physics Olympiad
  • 1987-present Member, American Physical Society
  • 1995-present Member, Materials Research Society
  • 2000-present Member, Fellow, Korean Physical Society