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

Abstract

Programmable optical circuits form a key part of quantum technologies today, ranging from transceivers for quantum communication to integrated photonic chips for quantum information processing. As the size of such circuits is increased, maintaining precise control over every individual component becomes challenging, leading to a reduction in the quality of the operations performed. In parallel, minor imperfections in circuit fabrication are amplified in this regime, dramatically inhibiting their performance. Here we show how embedding an optical circuit in the higher-dimensional space of a large, ambient mode-mixer using inverse-design techniques allows us to forgo control over each individual circuit element, while retaining a high degree of programmability over the circuit. Using this approach, we implement high-dimensional linear optical circuits within a complex scattering medium consisting of a commercial multi-mode fibre placed between two controllable phase planes. We employ these circuits to manipulate high-dimensional spatial-mode entanglement in up to seven dimensions, demonstrating their application as fully programmable quantum gates. Furthermore, we show how their programmability allows us to turn the multi-mode fibre itself into a generalised multi-outcome measurement device, allowing us to both transport and certify entanglement within the transmission channel. Finally, we discuss the scalability of our approach, numerically showing how a high circuit fidelity can be achieved with a low circuit depth by harnessing the resource of a high-dimensional mode-mixer. Our work serves as an alternative yet powerful approach for realising precise control over high-dimensional quantum states of light, with clear applications in next-generation quantum communication and computing technologies.

Reconfigurable quantum-optical circuits in a complex medium

“…We use the top-down approach to describe the linear optical circuit as a transformation built from a cascade of optical mode mixers {U j } separated by phase shifters {P j }. In this approach, we embed a d-dimensional circuit T within these large complex mode-mixers U j with dimension n ≫ d. 5 A programmable circuit with depth L (the number of layers) is represented as:…”

“…The mode-mixers are placed between reprogrammable phase planes, which are programmed using an inverse-design approach. 5 This allows us to encode any high-dimensional unitary by harnessing the large dimensionality of the mode-mixers as an additional resource. In this work, we implement this architecture by placing a multi-mode fiber (MMF) between a pair of spatial light modulators (SLMs) to program a general unitary transformation.…”

Research on Sports Footwear Brand Image Based on Service Design

“…2)Service Design Principles The concept of service design follows certain principles and standards, but the conclusions given by different researchers on the principles of service design are different. The current service design principles that are more recognized in the industry are the five principles proposed by Mark and Jacob in 2011, including user-centeredness, collaborative innovation, orderliness, tangibility, and integrity (Goel et al, 2022). Then, in practical research, they found that the five principles were not enough to meet the industry requirements of service design, so they proposed new service design principles in 2018.…”

Revealing the Invisible: Imaging Through Non-Radiating Subspace

“…Inverse problems in electromagnetics, encompassing inverse source [1,2], inverse scattering [3][4][5][6], inverse design [7], and inverse synthesis [8] problems, have found widespread applications in various fields, including microwave imaging [9], radar tracking [10], breast cancer detecting [11], remote sensing [12], tomography [13], seismology [14], failure analysis [15], nondestructive evaluation [16], antenna design and pattern synthesis [17,18], nanoscale optical positioning [19], and integrated quantum photonics [20][21][22]. Among these, electromagnetic inverse scattering focuses on detecting, locating, shape finding, and material imaging of unknown objects using scattered fields and Maxwell's equations.…”