We present a new class of solutions based on quantum optical scattering in certain optical structures that may be applied in the development of photonic devices in one and two spatial dimensions. These devices may act as sensors for optical fibers by selecting appropriate wavelengths and acting as noise suppression for integrated devices and in the processing of quantum optical signals. We highlight that quantum optical scattering can be adequately modeled in order to describe the typical nonlinear optical effects of the photonic device and capable of describing a type of entanglement between Raman and Brillloin scatterings. This modeling among other applications could open a new window for hybrid sensors based on nonlinear optical effects in photonic optical structures and quantum optical scattering.
We present a new class of solutions based on quantum optical scattering in certain optical structures that may be applied in the development of photonic devices in one and two spatial dimensions. These devices may act as sensors for optical fibers by selecting appropriate wavelengths and acting as noise suppression for integrated devices and in the processing of quantum optical signals. We highlight that quantum optical scattering can be adequately modeled in order to describe the typical nonlinear optical effects of the photonic device and capable of describing a type of entanglement between Raman and Brillloin scatterings. This modeling among other applications could open a new window for hybrid sensors based on nonlinear optical effects in photonic optical structures and quantum optical scattering.
The interaction of light with matter can generate different types of scattering that can be applied to quantum optics, photonics and integrated optics appropriately. The generation of certain pulses in certain waveguides can produce certain nonlinear optical pulses with important properties such as low energy and information loss applied, for example, to communication systems and quantum information. The method we describe is based on the generation and propagation of nonlinear optical pulses in multidimensional material structures: waveguides in 1 dimension, planar systems in 2 dimensions and crystalline systems in 3 dimensions. These structures can be appropriately designed to generate nonlinear and quantum optical pulses depending on the crystal structure and electrical susceptibility of the material. These optical pulses can be appropriately characterized whose respective scattering signals can be identified and processed providing an application basis for emerging technologies for transmission and processing systems based on quantum optics and quantum computing.
Optical fibers are the backbone of the world's communication systems. They also represent the simplest example of a photonic device, where photons in waveguides replace electrons in wires. More sophisticated devices than this can be made, in which all the optical components – including multiple waveguided modes – are integrated on a chip. It is important to understand the quantum noise properties of these systems. While in some respects these systems can be treated as one-dimensional, there are additional features. Dispersion is due not just to material properties, but also to the waveguide geometry. The nonlinearity comes from a combination of material and geometric properties as well. There is, of course, a quantum aspect to these photonic devices, in which quantum noise occurs due to random effects caused by nonlinearity and gain. Optical devices based on waveguides are, of course, not just simple fibers. One can have multiple waveguides with various types of linear coupling. The intrinsic nonlinearity of the dielectric leads to four-wave mixing, which can be an important source of correlated photons, both for fundamental tests of quantum mechanics, and for applications in quantum information. It is often essential to include effects due to anisotropies of various types, as well as material dispersion. In dielectrics, another effect that should be included is the coupling of vibrational modes of the (solid) dielectric to the propagating field, which gives rise to Raman and Brillouin scattering effects. This allows us to obtain a more detailed and correct theory of quantum noise than the simplified case treated in Chapter 3.
Many components that are employed in quantum information and communication systems are well known photonic devices encountered in standard optical fiber communication systems, such as optical beamsplitters, waveguide couplers and junctions, electro-optic modulators and optical fiber links. The use of these photonic devices is becoming increasingly important especially in the context of their possible integration either in a specifically designed system or in an already deployed end-to-end fiber link. Whereas the behavior of these devices is well known under the classical regime, in some cases their operation under quantum conditions is less well understood. This paper reviews the salient features of the quantum scattering theory describing both the operation of the electro-optic phase and amplitude modulators in discrete and continuous-mode formalisms. This subject is timely and of importance in light of the increasing utilization of these devices in a variety of systems, including quantum key distribution and single-photon wavepacket measurement and conformation. In addition, the paper includes a tutorial development of the use of these models in selected but yet important applications, such as single and multi-tone modulation of photons, two-photon interference with phase-modulated light or the description of amplitude modulation as a quantum operation.
In this dissertation, multimode optical fibers (MMFs) have been studied as a robust and practical platform for nonlinear optics and quantum optics applications, where by experimental investigations and theoretical calculations we present the quantum and nonlinear virtue of MMFs as a versatile tool for future applications. Our investigations can be summarized in three parts: At first, we have investigated stimulated Raman scattering (SRS) in a long MMF, where more than 20 orders of cascaded Raman peaks have been generated. Observation of beam clean-up despite the highly multimode nature of the fiber and such strong nonlinear interaction despite the large fiber core size are distinguishable results of our work. Next, we have studied four-wave mixing (FWM) via intermodal phase-matching in both step-index and graded-index MMFs (GIMFs). A rigorous and general approach in the theoretical study is presented where some of the commonly used, yet inaccurate approximations are avoided. Experimentally, FWM side-bands with minimal contamination from SRS, and residual pump photons have been generated from quantum vacuum and amplified more than 11 orders of magnitude. Finally, in the last part of this dissertation, we have done a theoretical study of photon-pair generation in a multimode optical fiber (both step-index and GIMF) via intermodal-FWM as a source of state-engineered photon-pairs.
Quantum photonic resources are critical for advanced applications such as quantum computation, communication, and information processing. Efficient generation and detection of quantum states, as well as reliable photon manipulation techniques, are essential for the development of practical quantum technologies. Integrated photonic platforms offer attractive solutions due to their stability, small device footprint, and improved power efficiencies. However, optical loss and environmental noise hinder their capability to transmit, measure, and detect quantum states with high accuracies. To tackle these limitations, we have developed robust solutions for quantum signal processing by leveraging infrastructures from telecommunications and integrated photonics. These approaches focus on the use of silicon-based photonic sources for entanglement generation in the time and frequency degrees of freedom, as well as chip- and fiber-based architectures for entanglement verification via quantum interference and tomography measurements. Our photonic schemes allow for high-dimensional entanglement processing, demonstrating their versatility in developing scalable and cost-efficient quantum signal processing platforms.