Quantum-dot Cellular Automata as an Implementation for Random Number Generation

Quantum-dot Cellular Automata (QCA) provides a viable low-power alternative to conventional implementations of classical computing machines. QCA cells with no biasing voltage will yield a “1” or a “0” with a 50% chance of being “1” and 50% chance of being “0” upon measurement. Applying a bias voltage to a QCA cell allows this probability to be tuned such that the probability of measuring a “1” could range anywhere from 0 to 1. Many applications benefit from equal probabilities of measuring “0” or “1,” but some applications such as stochastic computing require having an adjustable probability of measurement outcomes. Performing a series of measurements can be used to serially create a random number of any desired size. Thus, tuning the probability of a QCA cell can be used as an implementation for random number generation. Furthermore, this system is suitable for applications in which zero outcome bias is desired, or a specific and dynamically-tunable bias is desired. We discuss the quantum mechanics of random number generation using a QCA cell, as well as different physical implementations for a QCA random number generator.