A universal fully reconfigurable 12-mode quantum photonic processor

Abstract

Photonic processors are pivotal for both quantum and classical information processing tasks using light. In particular, linear optical quantum information processing requires both large-scale and low-loss programmable photonic processors. In this paper, we report the demonstration of the largest universal quantum photonic processor to date: a low-loss 12-mode fully tunable linear interferometer with all-to-all mode coupling based on stoichiometric silicon nitride waveguides.

Certification of Gaussian Boson Sampling via graph theory

“…The method based on graph kernels requires fewer experiments with different graphs, in turn requiring the capability to tune the optical circuit U and the squeezing parameters s i . Nowadays, recent experimental results on integrated reconfigurable circuits [18,52,53] enable large tunability and dimension of the matrix U . In addition, squeezing parameters can be tuned by changing the power of the pump laser that generates squeezed light from nonlinear crystals, and by tuning the relative squeezing parameters phases as recently demonstrated in [5].…”

Observation of open scattering channels

“…One of the fiber couplers is placed on a linear stage (SLC-2475, Smaract GmbH) to achieve temporal overlap of the photons inside the chip. The optical chip consists of 12 input and 12 output modes and is fully tunable 27 . Once the photons have propagated through the chip, they are routed towards the superconducting nanowire single-photon detectors (SNSPD) (Photon Spot).…”

“…1a) and schematically in Fig. 1b) 27 . On this network, an entire scattering matrix S is implemented, where the first six output modes are treated as 'reflection' modes and output modes 7 − 12 as transmission modes.…”

Quantum simulation of thermodynamics in an integrated quantum photonic processor

“…Our interferometer is realized in silicon nitride waveguides [56,57], and has an overall size of n = 12 modes and an optical transmission of 2.2 − 2.7 dB, i.e., 54% − 60% depending on the input channel. Reconfigurability of the interferometer is achieved by a suitable arrangement of unit cells consisting of pairwise mode interactions realized as tunable Mach-Zehnder interferometers [58].…”

“…, where U set and U get are the intended and achieved unitary transformations in the processor, respectively. The processor preserves the secondorder coherence of the photons [57].…”