DOI: 10.1126/sciadv.adg7268ĭuring this study, Sund and colleagues focused on single-crystal lithium niobate thin films bonded on a silica insulating substrate as a promising platform due to their strong electrical-optical properties, high transparency and high index contrast to form integrated circuits.

Inset, schematic of the setup used in the measurement. The data show a 3-dB cutoff at approximately 6.5 GHz.

(F) Modulation bandwidth of the MZI measured with a VNA. (E) Schematic of the cross section of the electro-optic phase shifter. (D) Optical microscope image of an electrically tunable MZI. The inset shows a scanning electron micrograph image of the coupler. (C) Measured coupling efficiency of the fabricated grating couplers as a function of the input laser wavelength, with a peak efficiency of −3.4 dB. Color-coded is the field intensity of the fundamental TE waveguide mode. (A and B) Schematics of the designed waveguide geometry, tailored for the quantum emitter λ ≃ 940 nm operation wavelengths, for (A) SM waveguides used in bends and directional couplers, and (B) multimode straight waveguides. Researchers have recently developed solid-state quantum emitters such as quantum dots as near-ideal, high-efficiency sources of indistinguishable photons to realize on-demand single-photon sources. The high-quality photonic states and the fast, low-loss programmable circuits underlie the central idea of photonic quantum technologies to route and process applications. Photonics provide a promising platform to unlock scalable quantum hardware for long-range quantum networks with interconnections across multiple quantum devices and photonic circuits for quantum computing and simulation experiments. However, it is challenging to regulate quantum systems at scale for a variety of practical applications and also to form fault-tolerant quantum technologies. Quantum technologies have progressively advanced in the past several years to enable quantum hardware to compete with and surpass the capabilities of classical supercomputers. The results illustrate a promising direction in the development of scalable quantum technologies by merging integrated photonics with solid-state deterministic photon sources.Īdvances in quantum technologies with integrated photonics They processed the generated photons within low-loss circuits at speeds of several gigahertz and experimentally realized a variety of key photonic quantum information processing functionalities on high-speed circuits with inherent key features to develop a four-mode universal photonic circuit. The scientists integrated the platform with deterministic solid-state single photon sources using quantum dots in nanophotonic waveguides. In a new report now published in Science Advances, Patrik Sund and a research team at the center of hybrid quantum networks at the University of Copenhagen, and the University of Münster developed an integrated photonic platform with thin-film lithium niobate. Such platforms rely on low-loss, high-speed, reconfigurable circuits and near-deterministic resource state generators. Scalable photonic quantum computing architectures require photonic processing devices. Insets: Coincidence histograms for three different applied voltages. The HOM visibility of the quantum interference is determined from a curve fit (orange line) to be 92.7 ± 0.7%. The error bars are estimated from Poissonian statistics and are smaller than the data points. Minima and maxima in the observed HOM fringe correspond to applied phases of ϕ min = π/2 + kπ and ϕ max = kπ, respectively, with k an integer number. (B) Recorded coincidence data at zero time delay (shaded red areas in the insets) for varying applied voltages. The output photons are collected via the same fiber array and routed to SNSPDs for coincidence detection. Controlling the delay on one of the demultiplexer arms ensures that the photon pairs arrive at the device simultaneously, and fiber polarization controllers are used to optimize coupling into the TE mode. The photons are subsequently collected into fibers and injected into the LNOI chip by a fiber array. Photons generated by a QD SPS are sent into a two-mode demultiplexer consisting of a resonantly enhanced EOM and a polarizing beam splitter (PBS).

Measurement of on-chip quantum interference.

Peakhour setup router