TITLE:
Generation and Propagation of Ultrasonic Waves in Piezoelectric Graphene Nanoribbon
AUTHORS:
Musah Rabiu, Samuel Y. Mensah, Sulemana S. Abukari, Matthew Amekpewu, Baah Sefa-Ntiri, Anthony Twum
KEYWORDS:
Current Density; Negative Differential Conductivity; Commensurable Frequencies
JOURNAL NAME:
Open Journal of Acoustics,
Vol.3 No.3A,
September
12,
2013
ABSTRACT:
Generation and propagation of ultrasonic waves in single layer Graphene
Nanoribbon is studied using semi-classical approach. When piezoelectric Graphene
Nanoribbon (GNR) is exposed to time varying light beam, ultrasonic waves are
produced which propagate in the medium. At low frequencies, we observed
oscillations of the ultrasonic observables, velocity change
and attenuation which are characteristics of massless Dirac fermions in
graphene. Exploiting this oscillatory behavior, we estimate graphene’s electronic
mobility to be around . Propagating ultrasonic waves can be amplified, depending on
the electric field amplitude. Specifically, amplification occurs when drift
velocity exceeds sound velocity. This scheme can be employed for efficient
ultrasonic amplifier device operation.