TY - JOUR
T1 - Numerical experiments on phonon properties of isotope and vacancy-type disordered graphene
AU - Islam, Md Sherajul
AU - Ushida, Kenji
AU - Tanaka, Satoru
AU - Hashimoto, Akihiro
N1 - Funding Information:
This work was supported by a grant-in-aid of basic research (A) from the Ministry of Education, Culture, Sports, Science, and Technology, Japan .
PY - 2013
Y1 - 2013
N2 - We have studied phonon properties of graphene theoretically with different concentrations of 13C isotope and vacancy-type defects. The forced vibrational method, which is based on the mechanical resonance to extract the pure vibrational eigenmodes by numerical simulation, has been employed to compute the phonon density of states (PDOSs) and mode pattern of isotope-disordered graphene as well as a combined isotope and vacancy-type defective graphene structure. We observe a linear reduction of the E 2g mode frequencies with an increase in 13C concentration due to the reduced mass variation of the isotope mixture. We find a downshift of the E2g mode of 65 cm- 1, which is a very good agreement with the experimental results, and the phonon frequencies described by the simple harmonic oscillator model. The vacancy-type defects break down the phonon degeneracy at the ETH.
AB - We have studied phonon properties of graphene theoretically with different concentrations of 13C isotope and vacancy-type defects. The forced vibrational method, which is based on the mechanical resonance to extract the pure vibrational eigenmodes by numerical simulation, has been employed to compute the phonon density of states (PDOSs) and mode pattern of isotope-disordered graphene as well as a combined isotope and vacancy-type defective graphene structure. We observe a linear reduction of the E 2g mode frequencies with an increase in 13C concentration due to the reduced mass variation of the isotope mixture. We find a downshift of the E2g mode of 65 cm- 1, which is a very good agreement with the experimental results, and the phonon frequencies described by the simple harmonic oscillator model. The vacancy-type defects break down the phonon degeneracy at the ETH.
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U2 - 10.1016/j.diamond.2013.10.013
DO - 10.1016/j.diamond.2013.10.013
M3 - Article
AN - SCOPUS:84887769833
SN - 0925-9635
VL - 40
SP - 115
EP - 122
JO - Diamond and Related Materials
JF - Diamond and Related Materials
ER -