Nanoscale plasmonic phenomena in CVD-grown MoS2 monolayer revealed by ultra-broadband synchrotron radiation based nano-FTIR spectroscopy and near-field microscopy

Patoka, Piotr; Ulrich, Georg; Nguyen, Ariana E.; Bartels, Ludwig; Dowben, Peter A.; Turkowski, Volodymyr; Rahman, Talat S.; Hermann, Peter; Kastner, Bernd; Hoehl, Arne; Ulm, Gerhard; Ruhl, Eckart

doi:10.1364/OE.24.001154

Title: Nanoscale plasmonic phenomena in CVD-grown MoS₂ monolayer revealed by ultra-broadband synchrotron radiation based nano-FTIR spectroscopy and near-field microscopy

Journal Article · Wed Jan 13 00:00:00 EST 2016 · Optics Express

DOI:https://doi.org/10.1364/OE.24.001154· OSTI ID:1434579

Patoka, Piotr ^[1]; Ulrich, Georg ^[1]; Nguyen, Ariana E. ^[2]; Bartels, Ludwig ^[2]; Dowben, Peter A. ^[3]; Turkowski, Volodymyr ^[4]; Rahman, Talat S. ^[4]; Hermann, Peter ^[5]; Kastner, Bernd ^[5]; Hoehl, Arne ^[5]; Ulm, Gerhard ^[5]; Ruhl, Eckart ^[1]

Freie Univ., Berlin (Germany). Inst. for Chemistry and Biochemistry and Physical Chemistry
Univ. of California, Riverside, CA (United States). Dept. of Chemistry
Univ. of Nebraska, Lincoln, NE (United States). Dept. of Physics and Astronomy
Univ. of Central Florida, Orlando, FL (United States). Dept. of Physics
Physics-Technical Inst. (PTB), Berlin (Germany)

Here, nanoscale plasmonic phenomena observed in single and bi-layers of molybdenum disulfide (MoS₂) on silicon dioxide (SiO₂) are reported. A scattering type scanning near-field optical microscope (s-SNOM) with a broadband synchrotron radiation (SR) infrared source was used. We also present complementary optical mapping using tunable CO₂-laser radiation. Specifically, there is a correlation of the topography of well-defined MoS₂ islands grown by chemical vapor deposition, as determined by atomic force microscopy, with the infrared (IR) signature of MoS₂. The influence of MoS₂ islands on the SiO₂ phonon resonance is discussed. The results reveal the plasmonic character of the MoS₂ structures and their interaction with the SiO₂ phonons leading to an enhancement of the hybridized surface plasmon-phonon mode. A theoretical analysis shows that, in the case of monolayer islands, the coupling of the MoS₂ optical plasmon mode to the SiO₂ surface phonons does not affect the infrared spectrum significantly. For two-layer MoS₂, the coupling of the extra inter-plane acoustic plasmon mode with the SiO₂ surface transverse phonon leads to a remarkable increase of the surface phonon peak at 794 cm^-1. This is in agreement with the experimental data. These results show the capability of the s-SNOM technique to study local multiple excitations in complex non-homogeneous structures.

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Research Organization:: Univ. of Central Florida, Orlando, FL (United States)

Sponsoring Organization:: USDOE; German Research Foundation (DFG); Microelectronics Advanced Research Corp. (MARCO); Defense Advanced Research Projects Agency (DARPA)

Grant/Contract Number:: FG02-07ER15842; FG02-07ER46354; SFB 1112 (TP B02); SRC 2381.002; SRC 2381.003

OSTI ID:: 1434579

Journal Information:: Optics Express, Vol. 24, Issue 2; ISSN 1094-4087

Publisher:: Optical Society of America (OSA)Copyright Statement

Country of Publication:: United States

Language:: English

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Cited by: 29 works

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Title: Nanoscale plasmonic phenomena in CVD-grown MoS₂ monolayer revealed by ultra-broadband synchrotron radiation based nano-FTIR spectroscopy and near-field microscopy