  Chaos enables the emergence of randomness in deterministic physical systems.
Therefore it can be exploited for the conception of true random number
generators (RNG) mandatory in classical cryptography applications. Meanwhile,
nanomechanical oscillators, at the core of many on-board functionalities such
as sensing, reveal as excellent candidates to behave chaotically. This is made
possible thanks to intrinsic mechanical nonlinearities emerging at the
nanoscale. Here we present a platform gathering a nanomechanical oscillator and
its integrated capacitive actuation. Using a modulation of the resonant force
induced by the electrodes, we demonstrate chaotic dynamics and study how it
depends on the dissipation of the system. The randomness of a binary sequence
generated from a chaotic time trace is evaluated and discussed such that the
generic parameters enabling successful random number generation can be
established. This demonstration makes use of concepts which are sufficiently
general to be applied to the next generation of nano-electro-optomechanical
systems.
