This quantum CPU (quCPU?) is a big breakthrough, because quantum computers by definition are difficult to design. They're based on the concept of superposition — that a quantum bit, or qubit, can exist in two different states at once. Put another way, it can be a 0 or a 1 at the same time, and it can therefore perform calculations more quickly than a system based on 0 or 1. But it's hard to keep the qubits in a state in which this is possible, and interfering with them — i.e., reading their data — can destroy their superposition capabilities. So, a system that integrates random access memory into the qubits is a big step toward a working computer.