20-Mode Universal Quantum Photonic Processor

Abstract

Integrated photonics is an essential technology for optical quantum computing. Universal, phasestable, reconfigurable multimode interferometers (quantum photonic processors) enable manipulation of photonic quantum states and are one of the main components of photonic quantum computers in various architectures. In this paper, we report the realization of the largest quantum photonic processor to date. The processor enables arbitrary unitary transformations on its 20 input modes with a fidelity of (F Haar = 97.4%, F Perm = 99.5%), an average optical loss of 2.9 dB/mode, and high-visibility quantum interference (V HOM = 98%). The processor is realized in Si 3 N 4 waveguides.

A high-fidelity and large-scale reconfigurable photonic processor for NISQ applications

“…We obtain high values of statistical fidelities averaging above 93% for all considered input-output configurations and observe low variation in quality depending on the circuit at a fixed input size. This compares favorably with many alternative methods based on integrated circuits [23,25] at comparable output sizes and is close to recent demonstrations [26] for 26 outputs. The ease of scaling to a larger number of outputs is one significant advantage of the 3D wave-mixing approach, as leading re-configurable integrated systems are currently limited to our knowledge to 20x20 circuits.…”

“…They are needed to implement QIP both in circuit model [10] and cluster state approaches [11,12], and could find applications in diverse fields such as quantum transport [13][14][15][16], quantum repeaters [17], and quantum machine learning [18][19][20][21]. Photonic integrated circuits are a popular choice for the implementation of such systems [22][23][24][25][26].…”

Characterization of multimode linear optical networks

“…Our findings pave the way for the successful adoption of such an effective black-box methodology to large-scale optical networks, which nowadays are approaching a high number of optical modes and components, 19,22,23 with applications ranging from quantum communication and sensing to quantum computation and simulation via photonic systems.…”

“…Integrated photonics is one of the best candidates to realize such optical protocols in compact devices, offering, in addition, the capability to reconfigure the circuit operation. 11,21 The latest examples of multimode optical networks 22,23 have shown a significant increase in network complexity as well as in the number of control parameters.…”

Inverse-design of high-dimensional quantum optical circuits in a complex medium

“…1a). Over the past two decades, the technological development of integrated programmable circuits has enabled universal programmability in up to 20 path-encoded modes, containing a few hundreds of optical components on the same chip [9][10][11][12].…”