We use micro-Raman spectroscopy to study strain in free-standing graphene monolayers anchored to SiN holes of non-circular geometry. We show that a uniform differential pressure load yields measurable deviations from hydrostatic strain, conventionally observed in radially symmetric microbubbles. A pressure load of 1 bar yields a top hydrostatic strain of ≈ 0.7% and a G± splitting of 10 cm−1 in graphene clamped to elliptical boundaries with axes 40 and 20 μm, in good agreement with the calculated anisotropy Δε ≈ 0.6% and consistently with recent reports on Grüneisen parameters. The implementation of arbitrary strain configurations by designing suitable boundary clamping conditions is discussed.
Anisotropic straining of graphene using micropatterned SiN membranes / Francesca F., Settembrini; Francesco, Colangelo; Alessandro, Pitanti; Vaidotas, Miseikis; Camilla, Coletti; Guido, Menichetti; Renato, Colle; Giuseppe, Grosso; Alessandro, Tredicucci; Stefano, Roddaro. - In: APL MATERIALS. - ISSN 2166-532X. - STAMPA. - 4:(2016), pp. 116107-1-116107-7. [10.1063/1.4967937]
Anisotropic straining of graphene using micropatterned SiN membranes
COLLE, RENATO;
2016
Abstract
We use micro-Raman spectroscopy to study strain in free-standing graphene monolayers anchored to SiN holes of non-circular geometry. We show that a uniform differential pressure load yields measurable deviations from hydrostatic strain, conventionally observed in radially symmetric microbubbles. A pressure load of 1 bar yields a top hydrostatic strain of ≈ 0.7% and a G± splitting of 10 cm−1 in graphene clamped to elliptical boundaries with axes 40 and 20 μm, in good agreement with the calculated anisotropy Δε ≈ 0.6% and consistently with recent reports on Grüneisen parameters. The implementation of arbitrary strain configurations by designing suitable boundary clamping conditions is discussed.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
