Amplification of Acoustic Waves in Armchair Graphene Nanoribbon in the Presence of External Electric and Magnetic Field

Amplification of Acoustic Waves in Armchair Graphene Nanoribbon (AGNR) in the presence of an external Electric and Magnetic field was studied using the quantum kinetic equation. The general expression for the Amplification (Γ⊥/Γ0) was obtained in the region ql>> 1 for the energy dispersion ε(~p) near the fermi point. For various parameters of the quantized wave vector (β), the analysis of Γ⊥/Γ0 against the sub-bands index (pi); width of AGNR; and magnetic strength (φ), were numerically analysed. The results showed a linear relation for Γ⊥/Γ0 with constant electric field ( ~E) but non-linear for Γ⊥/Γ0 with q or φ. Sound Amplifica-tion by Stimulated Emission of Radiation (SASER) in AGNR is reported where an increase in Acoustic wave number (~q) causes intraband transition which modulates the Amplification