posted on 2019-01-25, 00:00authored byRobin
J. Dolleman, Pierpaolo Belardinelli, Samer Houri, Herre S. J. van der Zant, Farbod Alijani, Peter G. Steeneken
Stochastic switching
between the two bistable states of a strongly
driven mechanical resonator enables detection of weak signals based
on probability distributions, in a manner that mimics biological systems.
However, conventional silicon resonators at the microscale require
a large amount of fluctuation power to achieve a switching rate in
the order of a few hertz. Here, we employ graphene membrane resonators
of atomic thickness to achieve a stochastic switching rate of 4.1
kHz, which is 100 times faster than current state-of-the-art. The
(effective) temperature of the fluctuations is approximately 400 K,
which is 3000 times lower than the state-of-the-art. This shows that
these membranes are potentially useful to transduce weak signals in
the audible frequency domain. Furthermore, we perform numerical simulations
to understand the transition dynamics of the resonator and use analytical
expressions to investigate the relevant scaling parameters that allow
high-frequency, low-temperature stochastic switching to be achieved
in mechanical resonators.