Exploration of multiphoton entangled states by using weak nonlinearities

TL;DR

This paper introduces a practical scheme for generating multiphoton entangled states using linear optics and weak nonlinearities, reducing phase shift complexity and maintaining low error probabilities even with many photons.

Contribution

The proposed method simplifies multiphoton entanglement generation by using small phase shifts, making large-scale entangled states more feasible to produce.

Findings

Error probabilities remain low with increasing photon number

The scheme is more feasible than previous methods due to reduced phase shift complexity

Large multiphoton entangled states can be produced with high fidelity

Abstract

We propose a fruitful scheme for exploring multiphoton entangled states based on linear optics and weak nonlinearities. Compared with the previous schemes the present method is more feasible because there are only small phase shifts instead of a series of related functions of photon numbers in the process of interaction with Kerr nonlinearities. In the absence of decoherence we analyze the error probabilities induced by homodyne measurement and show that the maximal error probability can be made small enough even when the number of photons is large. This implies that the present scheme is quite tractable and it is possible to produce entangled states involving a large number of photons.