Optical neuromorphic computing marks a breakthrough over traditional digital computing by offering energy-efficient, fast, and parallel processing solutions while challenges remain in incorporating nonlinearity efficiently. Leveraging nonlinear wave dynamics in optical fibers as a computational resource may provide a solution. Our research demonstrates how femtosecond pulse propagation in optical fibers can emulate neural network inference, utilizing the high phase sensitivity of broadband light for creating nonlinear input-output mappings akin to Extreme Learning Machines (ELMs). Experimental results show high classification accuracies and low RMS errors in function regression, all at pico-joule pulse energy. This indicates our method's potential to lower energy consumption for inference tasks, complementing existing spatial-mode systems. We also investigated femtosecond pulses' nonlinear broadening effects – self-phase modulation and coherent soliton fission – demonstrating their distinct impacts on classification tasks and showcasing broadband frequency generation as a powerful, energy-efficient tool for next-generation computing.
Photonic graph states serve as promising resources in various measurement-based quantum computation and communication protocols, such as quantum repeaters. However, their realization with linear optics poses challenges due to the absence of deterministic photon-entangling gates in such platforms. A potential solution involves leveraging quantum emitters, such as quantum dots or NV centers, to establish entanglement and subsequently transfer it to the emitted photons. The design of a quantum circuit that implements the generation of a graph state within such a framework is highly non-trivial nonetheless. Here, we introduce a generation circuit optimization approach that leverages the concept of local equivalency of graphs and employs graph theoretical correlations to explore alternative, cost-effective circuits. Obtaining a 50% reduction in the use of 2-qubit gates for preparing repeater graph states highlights the potential efficacy of our method.
Quantum technologies harness nonclassical features of particles, here, photons, to develop novel, efficient, and precise devices for information processing applications. Superposition, entanglement, as well as the coherent manipulation of quantum states are at the heart of the second quantum revolution (quantum 2.0) which targets the development of secure cryptographic systems, complex computation protocols, and more. Emerging quantum architectures rely on the realistic implementation of photonic schemes which are scalable, resource-efficient, and compatible with CMOS technologies as well as fiber networks. This work demonstrates current schemes utilized for time-/frequency-bin entanglement generation and processing by leveraging existing telecommunications and integrated photonics infrastructures.
KEYWORDS: Holmium, Current controlled current source, Visualization, Blood circulation, Doppler tomography, Optical coherence tomography, Optical testing, Eye, In vivo imaging
Visually evoked changes of retinal blood flow can serve as an important research tool to investigate eye disease such as glaucoma and diabetic retinopathy. In this study we used a combined, research-grade, high-resolution Doppler OCT+ERG system to study changes in the retinal blood flow (RBF) and retinal neuronal activity in response to visual stimuli of different intensities, durations and type (flicker vs single flash). Specifically, we used white light stimuli of 10 ms and 200 ms single flash, 1s and 2s for flickers stimuli of 20% duty cycle. The study was conducted in-vivo in pigmented rats. Both single flash (SF) and flicker stimuli caused increase in the RBF. The 10 ms SF stimulus did not generate any consistent measurable response, while the 200 ms SF of the same intensity generated ~4% change in the RBF peaking at ~1.5 s after the stimulus onset. Single flash stimuli introduced ~2x smaller change in RBF and ~30% earlier RBF peak response compared to flicker stimuli of the same intensity and duration. Doubling the intensity of SF or flicker stimuli increased the RBF peak magnitude by ~1.5x. Shortening the flicker stimulus duration by 2x increased the RBF recovery rate by 2x, however, had no effect on the rate of RBF change from baseline to peak.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.