I'm not sure which exactly was the very first one. But some well - known quantum - themed fiction books include 'The Quantum Thief' by Hannu Rajaniemi. It has elements of quantum mechanics intertwined with a really interesting heist story.
It's difficult to name the very first quantum fiction book. But 'A Wrinkle in Time' by Madeleine L'Engle has some elements that could be related to quantum concepts, like the idea of traveling through different dimensions and the bending of space - time. It's a classic children's book that has a lot of depth and could be considered an early forerunner in terms of using such complex scientific - like ideas in fiction.
There are many books that touch on quantum concepts, but it's hard to pinpoint the first. However, 'Schrödinger's Cat Trilogy' by Robert Anton Wilson is quite an old and interesting one that plays with quantum ideas. It's a wild and thought - provoking read that combines different philosophical and scientific concepts related to quantum theory.