A family of quantum von Neumann architecture

TL;DR

This work develops universal quantum computing models that form a family of quantum von Neumann architectures, with modular units of memory, control, CPU, and internet, besides input and output, that serves as a unique approach to building universal quantum computers.

Abstract

In this work, we develop universal quantum computing models that form a family of quantum von Neumann architecture, with modular units of memory, control, CPU, internet, besides input and output. This family contains three generations characterized by dynamical quantum resource theory, and it also circumvents no-go theorems on quantum programming and control. Besides universality, such a family satisfies other desirable engineering requirements on system and algorithm designs, such as the modularity and programmability, hence serves as a unique approach to build universal quantum computers.

Figures (4)

• Figure 1: Schematics of the functionality of quantum von Neumann architecture. They are the Program, Control, CPU, Input and Output units, with colors of yellow, blue, red, orange, and green, respectively. Besides, quantum internet is also needed to communicate quantum data.
• Figure 2: Schematics of a circuit in QvN-II. The evolution of each qubit defines a local part, with the entangling gates (vertical lines) as universal resources. The connection between any two programs is a composition via standard (blue box) or $SU(2)$ covariant (red box) teleportation. A black dot represents a qubit gate.
• Figure 3: (a) The information flow in QvN-II. Each box is a composition. (b) Schematics for the switchability. (c) A switchable program with an "on" path (green) and "off" path (red). Vertical lines represent CNOT gates, or CZ gates equivalently. The black dot is a qubit program, and the black crossing wires represent the swap gate. This scheme also applies to the CNOT program.
• Figure 4: Schematics for the model of QvN-III. The bold wires are multiple ebits, $\eta_{\hat{U}}$ with control to $\hat{U}$ represents the covariant POVM, $\Phi$ represents the circuit to prepare the generalized sine state. The grey part forms the program $\omega_\text{cov}$. Note we have rotated the diagram for convenience.