Double-slit implementation of minimal Deutsch algorithm

TL;DR

This paper demonstrates an experimental implementation of the minimal Deutsch algorithm using optical methods, encoding a qubit in spatial modes and employing a spatial light modulator to perform the necessary quantum operations.

Contribution

It presents the first optical realization of the minimal Deutsch algorithm with a single qubit, utilizing spatial light modulation and heralded single photons.

Findings

Successful implementation of the minimal Deutsch algorithm in an optical setup

Use of a spatial light modulator to generate one-bit functions

Potential for future quantum protocol implementations using SLMs

Abstract

We report an experimental implementation of the minimal Deutsch algorithm in an optical setting. In this version, a redundancy is removed from the most famous form of the algorithm. The original version involves manipulation of two qubits, while in its minimal version, only one qubit is used. Our qubit is encoded in the transversal spatial modes of a spontaneous parametric down-converted signal photon, with the aid of a double slit, with the idler photon playing a crucial role in creating a heralded single photon source. A spatial light modulator (SLM) is programmed to physically generate one-bit functions necessary to implement the algorithm's minimal version, which shows that the SLM can be used in future implementations of quantum protocols.