Time interleaved optical sampling for ultra-high speed A/D conversion

A scheme is proposed for increasing the sampling rate of analogue-to-digital conversion by more than an order of magnitude by combining state-of-the-art A/D converters with photonic technology. Ultra-high speed sampling is performed optically by a multiwavelength pulse train. Wavelength demultiplexers convert the high repetition rate data stream of samples into parallel data streams that can be handled by available electronic A/D converters

Gas Source Molecular Beam Epitaxy of Compound Semiconductors

Contains an introduction and reports on seven research projects.Defense Advanced Research Projects Agency Subcontract 284-25041Joint Services Electronics Program Contract DAAL04-95-1-0038National Center for Integrated Photonic Technology Contract 542-381U.S. Army Research Office/ AASERT Contract DAAH04-93-G-0175National Science Foundation Grant DMR 92-02957Joint Services Electronics Program Grant DAAL04-95-1-0038National Science Foundation Grant DMR 90-22933National Science Foundation Grant DMR 92-02957National Center for Integrated Photonic Technology Contract 542-381MIT Lincoln LaboratoryNational Center for Integrated Photonic Technology Subcontract 542-383National Science Foundation DMR 94-0033

The Orbital Angular Momentum of Light for Ultra-High Capacity Data Centers

The potential of orbital angular momentum (OAM) of light in data center scenarios is presented. OAMs can be exploited for short reach ultra-high bit rate fiber links and as additional multiplexing domain in transparent ultra-high capacity optical switches. Recent advances on OAM integrated photonic technology are also reported. Finally demonstration of OAM-based fiber links (aggregate throughput 17.9 Tb/s) and two layers OAM-WDM-based optical switches are presented exploiting OAM integrated components and demonstrating the achievable benefits in terms of size, weight and power consumption (SWaP) compared to different technologies

Photonic Technology for Precision Metrology

Photonics has had a decisive influence on recent scientific and technological achievements. It includes aspects of photon generation and photon–matter interaction. Although it finds many applications in the whole optical range of the wavelengths, most solutions operate in the visible and infrared range. Since the invention of the laser, a source of highly coherent optical radiation, optical measurements have become the perfect tool for highly precise and accurate measurements. Such measurements have the additional advantages of requiring no contact and a fast rate suitable for in-process metrology. However, their extreme precision is ultimately limited by, e.g., the noise of both lasers and photodetectors. The Special Issue of the Applied Science is devoted to the cutting-edge uses of optical sources, detectors, and optoelectronics systems in numerous fields of science and technology (e.g., industry, environment, healthcare, telecommunication, security, and space). The aim is to provide detail on state-of-the-art photonic technology for precision metrology and identify future developmental directions. This issue focuses on metrology principles and measurement instrumentation in optical technology to solve challenging engineering problems

Tapering of fs Laser-written Waveguides

The vast development of integrated quantum photonic technology enables the implementation of compact and stable interferometric networks. In particular laser-written waveguide structures allow for complex 3D-circuits and polarization-encoded qubit manipulation. However, the main limitation for the scale-up of integrated quantum devices is the single-photon loss due to mode-profile mismatch when coupling to standard fibers or other optical platforms. Here we demonstrate tapered waveguide structures, realized by an adapted femtosecond laser writing technique. We show that coupling to standard single-mode fibers can be enhanced up to 77% while keeping the fabrication effort negligible. This improvement provides an important step for processing multi-photon states on chip

Future broadband access network challenges

Copyright @ 2010 IEEEThe optical and wireless communication systems convergence will activate the potential capacity of photonic technology for providing the expected growth in interactive video, voice communication and data traffic services that are cost effective and a green communication service. The last decade growth of the broadband internet projects the number of active users will grow to over 2 billion globally by the end of 2014. Enabling the abandoned capacity of photonic signal processing is the promising solution for seamless transportation of the future consumer traffic demand. In this paper, the future traffic growth of the internet, wireless worldwide subscribers, and the end-users during the last and next decades is investigated. The challenges of the traditional access networks and Radio over Fiber solution are presented

Gas Source Molecular Beam Epitaxy of Compound Semiconductors

Contains an introduction and reports on seven research projects.Advanced Research Projects Agency Subcontract 284-25041Joint Services Electronics Program Contract DAAL03-92-C-0001Joint Services Electronics Program Grant DAAH-04-95-1-0038National Center for Integrated Photonic Technology Contract 542-381National Center for Integrated Photonic Technology Grant subcontract 652-693U.S. Army Research Office/ AASERT Contract DAAH04-93-G-0175National Science Foundation Grant DMR 92-02957National Science Foundation Grant DMR 92-02957National Science Foundation Grant DMR 90-22933MIT Lincoln Laboratory Contract BX-5411National Science Foundation DMR 94-0033

Multimode interference filter to solve degradation on coupler common-mode rejection

After quantifying degradation of a common mode rejection ratio (CMRR) 3dB-coupler due to excitation of TE01 mode, a novel compact circuit including multimode interference (MMI) coupler+bend+MMI+filter (CBF) is proposed. We show a CBF circuit has better CMRR at the expense of moderate loss. A complete tolerance analysis to main geometrical parameters has also been carried out.Publicad

Questions on the Structure of Perfect Matchings inspired by Quantum Physics

We state a number of related questions on the structure of perfect matchings. Those questions are inspired by and directly connected to Quantum Physics. In particular, they concern the constructability of general quantum states using modern photonic technology. For that we introduce a new concept, denoted as inherited vertex coloring. It is a vertex coloring for every perfect matching. The colors are inherited from the color of the incident edge for each perfect matching. First, we formulate the concepts and questions in pure graph-theoretical language, and finally we explain the physical context of every mathematical object that we use. Importantly, every progress towards answering these questions can directly be translated into new understanding in quantum physics.Comment: 10 pages, 4 figures, 6 questions (added suggestions from peer-review

Quantum Experiments and Graphs III: High-Dimensional and Multi-Particle Entanglement

Quantum entanglement plays an important role in quantum information processes, such as quantum computation and quantum communication. Experiments in laboratories are unquestionably crucial to increase our understanding of quantum systems and inspire new insights into future applications. However, there are no general recipes for the creation of arbitrary quantum states with many particles entangled in high dimensions. Here, we exploit a recent connection between quantum experiments and graph theory and answer this question for a plethora of classes of entangled states. We find experimental setups for Greenberger-Horne-Zeilinger states, W states, general Dicke states, and asymmetrically high-dimensional multipartite entangled states. This result sheds light on the producibility of arbitrary quantum states using photonic technology with probabilistic pair sources and allows us to understand the underlying technological and fundamental properties of entanglement.Comment: 7 pages, 7 figures; Appendix 3 pages, 5 figure