Probing electronic lifetimes and phonon anharmonicities in high-quality chemical vapor deposited graphene by magneto-Raman spectroscopy

Abstract

We present a magneto-Raman study on high-quality single-layer graphene grown by chemical vapor deposition (CVD) that is fully encapsulated in hexagonal boron nitride by a dry transfer technique. By analyzing the Raman D, G, and 2D peaks, we find that the structural quality of the samples is comparable to state-of-the-art exfoliated graphene flakes. From B field dependent Raman measurements, we extract the broadening and associated lifetime of the G peak due to anharmonic effects. Furthermore, we determine the decay width and lifetime of Landau level (LL) transitions from magneto-phonon resonances as a function of laser power. At low laser power, we find a minimal decay width of 140 1/cm highlighting the high electronic quality of the CVD-grown graphene. At higher laser power, we observe an increase of the LL decay width leading to a saturation with the corresponding lifetime saturating at a minimal value of 18 fs.

References in corpus (5)

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Cited by in corpus (5)

• Impact of Many-Body Effects on Landau Levels in Graphene
• Line Shape of the Raman 2D Peak of Graphene in Van Der Waals Heterostructures
• Charge carrier density-dependent Raman spectra of graphene encapsulated in hexagonal boron nitride
• Theory of resonant Raman scattering: Toward a comprehensive \textit{ab initio} description
• Many-body effects in suspended graphene probed through magneto-phonon resonances