Quantum computer of wire circuit architecture

TL;DR

This paper proposes a novel wire circuit architecture for quantum computers using coupled atomic ensembles, enabling perfect quantum memory, efficient two-qubit gates, and scalable 2D/3D architectures operable at room temperature.

Contribution

It introduces a flexible wire circuit design with atomic ensembles for quantum computing, demonstrating perfect quantum memory, accelerated two-qubit gates, and scalable architectures.

Findings

Perfect storage of photon qubits demonstrated experimentally.

Efficient two-qubit gates realized with direct coupling and atomic frequency shifts.

Scalable 2D/3D architectures proposed for universal quantum computing.

Abstract

First solid state quantum computer was built using transmons (cooper pair boxes). The operation of the computer is limited because of using a number of the rigit cooper boxes working with fixed frequency at temperatures of superconducting material. Here, we propose a novel architecture of quantum computer based on a flexible wire circuit of many coupled quantum nodes containing controlled atomic (molecular) ensembles. We demonstrate wide opportunities of the proposed computer. Firstly, we reveal a perfect storage of external photon qubits to multi-mode quantum memory node and demonstrate a reversible exchange of the qubits between any arbitrary nodes. We found optimal parameters of atoms in the circuit and self quantum modes for quantum processing. The predicted perfect storage has been observed experimentally for microwave radiation on the lithium phthalocyaninate molecule ensemble. Then also, for the first time we show a realization of the efficient basic two-qubit gate with direct coupling of two arbitrary nodes by using appropriate atomic frequency shifts in the circuit nodes. Proposed two-qubit gate runs with a speed drastically accelerated proportionally to the number of atoms in the node. The direct coupling and accelerated two-qubit gate can be realized for large number of the circuit nodes. Finally, we describe two and three-dimensional scalable architectures that pave the road to construction of universal multi-qubit quantum computer operating at room temperatures.