A single-interaction step implementation of a quantum search in coupled micro-cavities

TL;DR

This paper proposes a highly efficient implementation of Grover's quantum search algorithm using coupled micro-cavities with three-level atoms, achieving a single-step operation that scales with the square root of the database size.

Contribution

It introduces a method to realize the reflection operator for quantum search in a single physical step using coupled cavities and global laser fields, improving operational efficiency.

Findings

Single-interaction step implementation of Grover's algorithm

Robustness against photon loss and cavity frequency fluctuations

Operation scales as O(√N) with database size

Abstract

We present a method for realizing efficiently Grover's search algorithm in an array of coupled cavities doped with three-level atoms. We show that by encoding information in the lowest two ground states of the dopants and through the application of appropriately tuned global laser fields, the reflection operator needed for the quantum search algorithm can be realized in a single physical operation. Thus, the time steps in which Grover's search can be implemented become equal to the mathematical steps ~ O(\sqrt{N}), where N is the size of the register. We study the robustness of the implementation against errors due to photon losses and fluctuations in the cavity frequencies and atom-photon coupling constants.