  Random numbers are important in many activities, including communication,
encryption, science, gambling, finance, and decision-making. There is a strong
demand for a hardware random number generator that could support cryptographic
applications. In this work, we propose a quantum tunneling diode as a source of
true randomness achieved by applying electrical current sweeps through the
device and then harnessing a time-counting unit to measure fluctuation of
current flows. Our approach can be implemented with inexpensive electronics and
could be integrated into systems that require random numbers such as portable
communication devices.

Applied Physics