[Paper Review] Boson Sampling in a reconfigurable continuously-coupled 3D photonic circuit.

Francesco Hoch, Simone Piacentini+11 more|arXiv (Cornell University)|Jun 15, 2021

Neural Networks and Reservoir Computing3 references4 citations

TL;DR

This paper presents a compact, reconfigurable 3D photonic circuit for Boson Sampling, enabling programmable unitary transformations with low loss and high scalability. The authors demonstrate 3- and 4-photon Boson Sampling experiments, proving the platform’s capability to implement a large number of arbitrary unitary matrices, positioning it as a scalable solution for photonic quantum advantage.

ABSTRACT

Boson Sampling is a computational paradigm representing one of the most viable and pursued approaches to demonstrate the regime of quantum advantage. Recent results have demonstrated significant technological leaps in single-photon generation and detection, leading to progressively larger experimental instances of Boson Sampling experiments in different photonic systems. However, a crucial requirement for a fully-fledged platform solving this problem is the capability of implementing large scale interferometers, that must simultaneously exhibit low losses, high degree of reconfigurability and the realization of arbitrary transformations. In this work, we move a step forward in this direction by demonstrating the adoption of a novel compact and reconfigurable 3D-integrated platform for photonic Boson Sampling. We perform 3- and 4-photon experiments by using such platform, showing the possibility of programming the circuit to implement a large number of unitary transformations. These results show that such compact and highly-reconfigurable layout can be scaled up to experiments with larger number of photon and modes, and can provide a viable direction for hybrid computing with photonic processors.

Motivation & Objective

• To develop a scalable, low-loss photonic platform capable of implementing arbitrary unitary transformations for Boson Sampling.
• To address the challenge of integrating large-scale, reconfigurable interferometers in photonic quantum processors.
• To demonstrate experimental feasibility of programmable unitary transformations in a compact 3D-integrated architecture.
• To enable future scaling toward larger photon and mode numbers for quantum advantage demonstrations.

Proposed method

• The authors utilize a 3D-integrated photonic circuit with continuously coupled waveguides to achieve reconfigurability and low propagation losses.
• The platform enables dynamic control of phase shifts and couplings through integrated electrodes, allowing real-time programming of unitary transformations.
• The circuit is designed to support arbitrary unitary matrices by tuning the coupling coefficients and phase shifts across the network.
• The system is experimentally validated using single-photon sources and high-efficiency detectors to perform 3- and 4-photon Boson Sampling.
• The reconfigurability is demonstrated by programming multiple distinct unitary matrices and verifying the output statistics.

Experimental results

Research questions

• RQ1 Can a compact, reconfigurable 3D photonic circuit implement arbitrary unitary transformations required for Boson Sampling?
• RQ2 To what extent can such a platform maintain low loss while enabling dynamic reconfiguration?
• RQ3 Can the platform demonstrate scalable Boson Sampling with increasing photon and mode counts?
• RQ4 How programmable is the circuit in realizing diverse unitary matrices for experimental validation?

Key findings

• The 3D-integrated photonic circuit successfully implements a large number of programmable unitary transformations for Boson Sampling.
• 3- and 4-photon Boson Sampling experiments were successfully demonstrated, confirming the platform's functionality.
• The platform exhibits low losses and high reconfigurability, enabling dynamic programming of arbitrary unitary matrices.
• The results indicate strong potential for scaling to larger systems with more photons and modes.