Classical modelling of a bosonic sampler with photon collisions

TL;DR

This paper introduces a classical algorithm for simulating bosonic samplers that accounts for photon collisions, outperforming existing algorithms especially when collisions are frequent.

Contribution

It presents a new classical simulation method for bosonic sampling that is more efficient in collision-heavy regimes, addressing a gap in prior algorithms.

Findings

Algorithm outperforms existing methods with photon collisions

Effective in regimes with high photon collision rates

Provides a new tool for classical simulation of bosonic systems

Abstract

When the problem of boson sampling was first proposed, it was assumed that little or no photon collisions occur. However, modern experimental realizations rely on setups where collisions are quite common, i.e. the number of photons $M$ injected into the circuit is close to the number of detectors $N$. Here we present a classical algorithm that simulates a bosonic sampler: it calculates the probability of a given photon distribution at the interferometer outputs for a given distribution at the inputs. This algorithm is most effective in cases with multiple photon collisions, and in those cases it outperforms known algorithms.