Quantum computing has come on in leaps and bounds in the last few years. Indeed, once the big technology companies like IBM, Microsoft, and Google started showing an interest, I kind of stopped keeping track. Nevertheless, research on the basic elements of quantum computing continues and is, for me, more interesting than the engineering achievements of commercial labs (which are still absolutely necessary).

In line with my interests, a group of researchers demonstrated the first quantum memristor recently. This may be a critical step in bringing a type of highly efficient neural network to the world of quantum computing without an eye-watering large number of quantum connections.

Memristors and adding the quantum

The concept of the memristor dates back to the 1970s, but, for a long time, it sat like a sock under your washing machine: forgotten and un-missed. The essential idea is that the current that flows through a memristor doesn’t just depend on the voltage that is applied across the terminals but also on the history of applied voltage. Physical implementations of memristors offer great promise for low-energy computing because they can be used to make energy-efficient memory.