Integrated photonic platform for quantum information with continuous variables

TLDR

Integrated quantum photonics offers a scalable platform for generating, manipulating, and detecting optical quantum states within miniaturized waveguide circuits. The study demonstrates generation, manipulation, and interferometric homodyne detection of nonclassical light on a single device, advancing a fully integrated continuous‑variable quantum information platform. The platform employs a dynamically reconfigurable lithium niobate waveguide network to generate and characterize squeezed vacuum and two‑mode entangled states. The device achieves –1.38 ± 0.04 dB squeezing, verifies entanglement with an inseparability criterion I = 0.77 ± 0.02 < 1, and demonstrates the ability to implement all processes needed for optical quantum technology, making it suitable for time‑encoded continuous‑variable cluster‑state quantum computation.

Abstract

Integrated quantum photonics provides a scalable platform for the generation, manipulation, and detection of optical quantum states by confining light inside miniaturized waveguide circuits. Here, we show the generation, manipulation, and interferometric stage of homodyne detection of nonclassical light on a single device, a key step toward a fully integrated approach to quantum information with continuous variables. We use a dynamically reconfigurable lithium niobate waveguide network to generate and characterize squeezed vacuum and two-mode entangled states, key resources for several quantum communication and computing protocols. We measure a squeezing level of - 1.38 ± 0.04 dB and demonstrate entanglement by verifying an inseparability criterion I = 0.77 ± 0.02 < 1. Our platform can implement all the processes required for optical quantum technology, and its high nonlinearity and fast reconfigurability make it ideal for the realization of quantum computation with time encoded continuous-variable cluster states.