Quantum Coherence Applications in Photonic Engineering

PASSING FRAGILE QUANTUM STATES BETWEEN SEPARATE PHOTON SOURCES OR TRUE QUANTUM TELEPORTATION? Quantum communication aims to enable secure transmission of information across large distances by exploiting the principles of quantum mechanics. A central protocol in this context is quantum teleportation, which allows the transfer of quantum states without requiring the physical transport of the particles themselves. The essence of this process lies in maintaining quantum coherence—the stable phase relationships among superposed states—which ensures that the delicate correlations defining the quantum information are preserved during transmission. When photons originate from distinct sources, the challenge becomes even more formidable: the quantum states must remain indistinguishable and their superposition structures intact, so that interference and entanglement can be reliably established. Without coherence, the fragile quantum information encoded in superposition collapses into classical noise, undermining the fidelity of teleportation. Thus, overcoming issues of indistinguishability and coherence is not simply a technical detail but the fundamental requirement for faithfully transferring quantum states between separate photon sources. Recent experimental work using semiconductor quantum dots (QDs) has addressed this challenge. Researchers demonstrated photonic quantum teleportation between photons emitted by two separate GaAs quantum dots. In this scheme, one QD acted as a single-photon source, while the other generated entangled photon pairs. The single photon was prepared in conjugate polarization states and interfaced with the biexciton emission of the entangled pair through a polarization-selective Bell state measurement. This process enabled the polarization state of the single photon to be teleported onto the exciton emission of the entangled pair. A significant technical obstacle was the frequency mismatch between the two photon sources. This was mitigated using polarization-preserving quantum frequency converters, which aligned the photons to telecommunication wavelengths. The experiment achieved remote two-photon interference with a visibility of 30(1)% and a post-selected teleportation fidelity of 0.721(33), exceeding the classical limit. These results indicate that quantum coherence and superposition were preserved across distinct sources, consistent with successful teleportation. Unlike classical communication, quantum protocols provide intrinsic security, as attempts to intercept signals introduce detectable disturbances. Thus, while challenges remain in scaling and improving fidelity, this work shows that quantum teleportation between distinct photon sources is not merely state transfer but genuine teleportation, marking a step toward practical quantum communication networks. # https://lnkd.in/eBN4PTeC

High-quality (Q)-factor optical resonators with extreme temporal coherence are of both technological and fundamental importance in optical metrology, continuous-wave lasing, and semiconductor quantum optics. Despite exten-sive efforts in designing high-Q resonators across different spectral regimes, the experimental realization of very large Q-factors at visible wavelengths remains challenging due to the small feature size that is sensitive to fabrication imperfections, and thus is typically implemented in integrated photonics. In the pursuit of free-space optics with the benefits of large space-bandwidth product and massive parallel operations, in a paper published in Nature Communication, we design and fabricate a near-visible-wavelength etch-free metasurface with minimized fabrication defects and experimentally demonstrate a million-scale ultrahigh-Q resonance. A new laser-scanning momentum-space-resolved spectroscopy technique with extremely high spectral and angular resolution is developed to characterize the record-high Q-factor as well as the dispersion of the million-Q resonance in free space. By integrating monolayer WSe2 into our ultrahigh-Q meta-resonator, we further demonstrate laser-like highly unidirectional and narrow-linewidth exciton emission, albeit without any operating power density threshold. Under continuous-wave laser pumping, we observe pump-power-dependent linewidth narrowing at room temperature, indicating the potential of our meta-optics platform in controlling coherent quantum light-sources. Our result also holds great promise for applications like optical sensing, spectral filtering, and few-photon nonlinear optics. This is a collaborative effort supported by Center for Integration of Modern Optoelectronic Materials on Demand (IMOD), NSF STC. You can find the paper here: https://rdcu.be/d1NLb. This work was performed in collaboration with Vinod Menon, Andrea Alù and Yuebing Zheng group.

A breakthrough in quantum research has demonstrated how synthetic dimensions can be used to efficiently process quantum information, offering new possibilities for quantum computing and communications. The study, published in Nature Photonics, presents a novel method for manipulating photonic states of light, enabling enhanced control over photon propagation. This increased control improves the detection of photon coincidences and boosts system efficiency, bringing researchers closer to scalable and practical quantum systems. The research, co-led by Professor Roberto Morandotti of the Institut national de la recherche scientifique (INRS) in collaboration with teams from Germany, Italy, and Japan, leverages the concept of quantum walks. These quantum walks, which have been integral to the development of quantum computing over the past two decades, increase the speed and complexity of quantum algorithms. The integration of synthetic photonic networks into this framework marks a significant advancement in the field. Synthetic photonic networks allow photons to interact in “synthetic dimensions,” a concept that adds layers of flexibility and control over quantum systems. By exploring these dimensions, researchers uncovered unexpected properties of photonic behavior, providing a platform for designing more robust and efficient quantum systems. This innovation builds on the principles of quantum walks, enhancing their application in computational and communication tasks. This breakthrough represents a pivotal step toward practical quantum technologies, as it simplifies the manipulation of quantum information while increasing efficiency. The ability to control photon states with such precision could accelerate advancements in quantum computing, secure communications, and beyond, setting the stage for future innovations in how information is processed and transmitted in quantum systems.

Researchers at INRS have developed a synthetic photonic lattice capable of generating and manipulating quantum states of light, paving the way for promising advancements in applications ranging from quantum computing to secure quantum communication protocols. A study co-directed by Professor Roberto Morandotti of Institut national de la recherche scientifique (INRS) in collaboration with teams from Germany, Italy, and Japan paves the way for innovative solutions that could enable the development of a system to process quantum information with both simplicity and power. Their work, just published in the journal Nature Photonics, presents a method for manipulating the photonic states of light in a never-before-seen way, offering greater control over the evolution of photon propagation. This control makes it possible to improve the detection and number of photon coincidences, as well as the efficiency of the system. Central to the research team’s experiments is the concept of quantum walks. “The development of the field of quantum computing, which began some twenty years ago, has benefited greatly from the notion of quantum walks, which are known to increase the speed and complexity of computer algorithms,” explains Professor Roberto Morandotti, whose laboratory is based at the INRS Énergie Matériaux Télécommunications Research Centre. Recently, the scientific community developed another concept: synthetic photonic networks. “This work enables us to use the concept of synthetic photonics dimensions to explore many quantum phenomena at the fundamental level, and to apply them to quantum technologies,” explains Stefania Sciara, a post-doc on Roberto Morandotti’s team and co-author of the study. The potential of this type of lattice was already known, for example, to simulate effects such as parity-time symmetry, superfluidity of light, and topological structures, but using conventional technology. “But despite their potential,” she adds, “a synthetic photonic lattice capable of handling quantum states had never been demonstrated.” This is precisely what Roberto Morandotti and his team have done. They have discovered a temporal synthetic photonic lattice capable of generating and manipulating quantum states of light (photons), using the concept of quantum walks in simple fiber systems. #quantum #communications #light #lattice #fibreoptics #photonics #breakthrough https://lnkd.in/gbtC_zRj

BREAKING NEWS: Scientists have achieved a major milestone in quantum physics by creating a photon that occupies thirty seven distinct quantum dimensions. This breakthrough demonstrates that individual particles of light can be engineered to store and process far more information than previously thought. In classical physics, a photon is described by simple properties such as wavelength, energy, and polarization. In quantum physics, however, photons can be assigned multiple states at once, forming high dimensional quantum systems that exceed the binary limits of qubits. To create the thirty seven dimensional photon, researchers used advanced optical setups that manipulated the particle’s spatial modes. By shaping the wavefront and allowing it to pass through precisely engineered patterns, they encoded the photon into thirty seven orthogonal states. Each state acts like a separate channel that can carry unique information. This significantly increases the data capacity and computational potential of quantum systems. High dimensional states also have advantages in noise resistance, making them more robust for communication. The experiment relied on interferometry and spatial light modulators to verify that the photon maintained coherent quantum behavior across all thirty seven dimensions. Measurements confirmed that the particle did not collapse into a lower dimensional state and that each encoded mode remained stable. This stability is essential for building quantum devices that depend on multitiered information structures. Applications of high dimensional photons include secure quantum communication, where more dimensions translate into stronger encryption. They may also enhance quantum computing by enabling more complex calculations within a single particle. In quantum teleportation and entanglement research, high dimensional states allow richer and more efficient information transfer. While this achievement is still experimental, it represents a critical step toward scalable quantum technologies. It shows that quantum systems are not limited to simple two state structures but can be expanded to dozens or even hundreds of dimensions with careful engineering. This progress moves the field closer to practical quantum networks and advanced computational platforms. #techmedtime #fblifestyle #quantumphysics #innovation #research

QuantLase LAB : Ultrafast laser pulses interacting with water at the molecular level unveil quantum phenomena crucial for quantum technologies. These pulses trigger nonlinear effects like multiphoton ionization, Raman scattering, and transient electronic excitations, leading to charge redistribution, quantum coherence, and localized plasma formation. The intense electric fields drive molecular wave packet evolution, enabling real-time manipulation of quantum superpositions and entanglement. This precise light-matter control paves the way for advancements in quantum sensing, ultrafast optical switches, and photonic quantum computing, offering new possibilities for secure communication, high-fidelity qubit control, and engineered quantum materials.

In quantum photonics, classical bitwise logic fails to capture the coherence of field-based systems. Fractal-Wave Algebra (FWA) introduces a paradigm where photons are not particles but multidimensional fields. Each photon contains 37 quantum measurements \(D_1\)–\(D_{37}\), acting as coordinated information channels. Resonance Operators (RO) enforce coherence across these dimensions, forming dynamic clusters that transcend geometry. A photonic AI lattice—e.g., a 16-ring microring chain on IMEC’s iSiPP50G platform—operates via RO-mediated synchronization. With coupling gap 200 nm, \(\kappa = 0.3\), \(\lambda = 1550\) nm, and Q = 10⁵, the system achieves coherence metric CM > 0.95 and error residue ER < 10⁻³. Broadband excitation (\(\Delta\lambda = 10\) nm) confirms self-locking behavior across spectral shifts. FWA operators—ℱ (fractal unfolding), ℛ (resonance coordination), ℰ (encoding), 𝒮 (compression), and 𝒯 (temporal phasing)—govern the evolution of the field. These allow dynamic activation, clustering, and modulation of the 37 dimensions, enabling robust, high-density encoding. RO ensures that perturbations (\(\delta\phi < 0.1\) rad) are compensated across the lattice. This architecture maps mathematical structures (e.g., Riemann zeros) into physical photonic patterns, enabling experimental mathematics and secure quantum processing. The observable output is a projection; true information density arises from coordinated activation of internal field states. Engineers must shift from particle logic to field reasoning: design = field configuration, testing = CM/ER metrics, algorithms = operator orchestration. Small-scale AI agents embedded in this lattice use the 37D space for predictive coordination beyond neural models. TRL‑4 prototypes are achievable via GDSII layouts, MPW submission, and interferometric phase mapping. Public specs (geometry, Q, FSR) remain reproducible; internal field algebra and kernel configurations stay protected. This duality supports both academic dissemination and secure deployment. FWA‑RO photonic AI redefines computation: photons become orchestrated fields, not bits. Coherence, resonance, and operator-driven control enable scalable, resilient, high-dimensional architectures—establishing a new standard for quantum photonics.

🔴 #Photon #Split into 37 #Quantum #Dimensions 🔶️ Physicists have manipulated light to exist in 37 quantum dimensions, using a fiber-based processor to link a photon's color and phase. 🔶️ This breakthrough uses 37 "informational layers" or modes (rather than physical spatial dimensions) to enhance #data #storage and #Quantum #Computing, representing a significant jump beyond classical, 3-D physics. 🔶️ #Methodology: Researchers used a fiber-based photonic processor and temporal multiplexing to control a single photon's properties, creating a 37-dimensional Hilbert space. 🔶️ #Purpose: To demonstrate a complex version of the Greenberger–Horne–Zeilinger (#GHZ) paradox, which highlights the contrast between Quantum and Classical computing. 🔶️ #Applications: By encoding information across 37 dimensions, this method could lead to #faster Quantum Computers, more #secure communication, and more #efficient simulations. 🔶️ #Significance: Demonstrates that photons can function as programmable structures, significantly increasing data carrying capacity beyond conventional optical systems. 🔶️ This is a major step in #Quantum #Optics, moving from testing quantum theory to creating practical, high-dimensional applications. (Original source: NASA, in https://lnkd.in/eJJstwx8 ) #innovation #technology #future #trends

We recently published a paper presenting a cavity-QED framework for the generation of squeezed light from semiconductor quantum dots integrated into microcavities. Our analysis identifies the operating conditions required to achieve amplitude-quadrature squeezing, with photon-number fluctuations reduced below the coherent-state limit. Squeezing levels of up to 5 dB are shown to be attainable using currently accessible QD and cavity parameters. We further demonstrate that quantum correlations arising from four-wave mixing play a dual role, simultaneously shaping the gain spectrum and enabling the generation of squeezing. Feel free to check it out. https://lnkd.in/eRtV7gjK UC Santa Barbara COPL - Centre d'optique, photonique et lasers Télécom Paris Université Laval

🚀 Revolutionizing Quantum Imaging: The Power of Spatial Biphoton States 🚀 🌟 Dive into the cutting-edge world of quantum photonics! A groundbreaking technique, akin to off-axis digital holography, enables us to capture the intricate dance of spatial biphoton states with unprecedented speed and fidelity. Here’s what you need to know: 🔍 Essence of the Discovery: High-Dimensional Quantum Applications: From secure quantum communications to high-precision metrology, spatial biphoton states are setting the stage for the next quantum leap. Innovative Imaging Technique: Utilizing a method called biphoton digital holography, we can now perform quantum state tomography three orders of magnitude faster than traditional methods, achieving an average fidelity of 87%! 📐 Core Equations Unveiled: State Superposition: Equation: "Ψ_TOTAL = Integral of [ψ_r(Xi, Xs) + ψ_u(Xi, Xs)] over all positions (Xi, Xs)" 📌 Meaning: Represents the superposition of a known reference state (ψ_r) with an unknown quantum state (ψ_u), enabling detailed phase and amplitude extraction. Subindexes: 'r' stands for 'reference', 'u' for 'unknown', 'Xi' for 'idler photon', and 'Xs' for 'signal photon'. 📌 Interference Pattern: Equation: "C(X1, X2) = |ψ_r(X1, X2) + ψ_u(X1, X2)|^2" Meaning: Shows interference patterns essential for reconstructing complex quantum states. Subindexes: Highlight the roles of the photons involved in generating the biphoton state. 🔬 Visual Highlights: Enhanced Imaging: Utilize less light and gain more information, pushing the boundaries of quantum imaging. Faster and More Reliable: Achieve detailed reconstructions of quantum states faster than ever before, crucial for both practical quantum computing and theoretical explorations. 🌐 Takeaways for Quantum Enthusiasts and Professionals: Leverage these insights to enhance your research or practical applications in quantum technologies. Explore new possibilities in quantum simulations and communications made feasible by high-dimensional state control. 🧠 Philosophical Insight: Yin and Yang of Quantum States: Just as the Yin and Yang symbolize harmony and balance in nature, the interference patterns in biphoton states reflect the profound balance of quantum entanglement. These images not only map physical states but also remind us of the interconnectedness of all things at the quantum level. 🔗 Read the full article for a deeper dive into the methodologies and impact of this research. Link here: https://lnkd.in/djppz3YC 🔊 Join the Conversation! Share your thoughts on how this breakthrough might shape the future of quantum technologies. Let's innovate together! #QuantumImaging #Photonics #QuantumLeap #InnovationInQuantum 👉 Stay updated with the latest in quantum physics and photonics by following our page!