Surpassing the Classical Limit in Magic Square Game with Distant Quantum Dots Coupled to Optical Cavities

TL;DR

This paper proposes an experimental setup using quantum dots in optical cavities to implement the Magic Square game, demonstrating quantum advantage over classical strategies even with realistic noise, and introduces a biased version of the game.

Contribution

It presents a feasible experimental design for quantum computation with quantum dots that surpasses classical limits in the Magic Square game under realistic conditions.

Findings

Quantum dots in optical cavities can implement MSG with current technology.

The setup outperforms classical strategies despite physical imperfections.

A biased version of the game can be achieved with additional information.

Abstract

The emergence of quantum technologies is heating up the debate on quantum supremacy, usually focusing on the feasibility of looking good on paper algorithms in realistic settings, due to the vulnerability of quantum systems to myriad sources of noise. In this vein, an interesting example of quantum pseudo-telepathy games that quantum mechanical resources can theoretically outperform classical resources is the Magic Square game (MSG), in which two players play against a referee. Due to noise, however, the unit winning probability of the players can drop well below the classical limit. Here, we propose a timely and unprecedented experimental setup for quantum computation with quantum dots inside optical cavities, along with ancillary photons for realizing interactions between distant dots to implement the MSG. Considering various physical imperfections of our setup, we first show that the MSG can be implemented with the current technology, outperforming the classical resources under realistic conditions. Next, we show that our work gives rise to a new version of the game. That is, if the referee has information on the physical realization and strategy of the players, he can bias the game through filtered randomness and increase his winning probability. We believe our work contributes to not only quantum game theory, but also quantum computing with quantum dots.