Breakthroughs In Photonics Research Articles

Spatiotemporal hologram

Spatiotemporal structured light has opened up new avenues for optics and photonics. Current spatiotemporal manipulation of light mostly relies on phase-only devices such as liquid crystal spatial light modulators to generate spatiotemporal optical fields with unique photonic properties. However, simultaneous manipulation of both amplitude and phase of the complex field for the spatiotemporal light is still lacking, limiting the diversity and richness of achievable photonic properties. In this work, a simple and versatile spatiotemporal holographic method that can arbitrarily sculpt the spatiotemporal light is presented. The capabilities of this simple yet powerful method are demonstrated through the generation of fundamental and higher-order spatiotemporal Bessel wavepackets, spatiotemporal crystal-like and quasi-crystal-like structures, and spatiotemporal flat-top wavepackets. Fully customizable spatiotemporal wavepackets will find broader application in investigating the dynamics of spatiotemporal fields and interactions between ultrafast spatiotemporal pulses and matters, unveiling previously hidden light-matter interactions and unlocking breakthroughs in photonics and beyond.

Acoustic Higher-Order Topological Insulators Induced by Orbital-Interactions.

The discovery of higher-order topological insulator metamaterials, in analogy with their condensed-matter counterparts, has enabled various breakthroughs in photonics, mechanics, and acoustics. A common way of inducing higher-order topological wave phenomena is through pseudo-spins, which mimic the electron spins as a symmetry-breaking degree of freedom. Here, this work exploits degenerate orbitals in acoustic resonant cavities to demonstrate versatile, orbital-selective, higher-order topological corner states. Type-II corner states are theoretically investigated and experimentally demonstrated based on tailored orbital interactions, without the need for long-range hoppings that has so far served as a key ingredient for Type-II corner states in single-orbital systems. Due to the orthogonal nature of the degenerate p orbitals, this work also introduces a universal strategy to realize orbital-dependent edge modes, featuring high-Q edge states identified in bulk bands. These findings provide an understanding of the interplay between acoustic orbitals and topology, shedding light on orbital-related topological wave physics, as well as its applications for acoustic sensing and trapping.

The role of photonics in energy

In celebration of the 2015 International Year of Light, we highlight major breakthroughs in photonics for energy conversion and conservation. The section on energy conversion discusses the role of light in solar light harvesting for electrical and thermal power generation; chemical energy conversion and fuel generation; as well as photonic sensors for energy applications. The section on energy conservation focuses on solid-state lighting, flat-panel displays, and optical communications and interconnects.

Breakthroughs in Photonics 2014

Breakthroughs in Photonics 2014

Breakthroughs in Photonics 2014: Semiconductor Luminescent Colloidal Core–Shell Nanorods and Dot-in-Rods

One-dimensional semiconductor colloidal nanostructures such as nanorods and core-shell dot-in-rods can now be synthesized with excellent chemical stability and photostability, large absorption cross section, reduced blinking, and high quantum efficiency. These structures have generated great interest because, compared to spherical nanocrystals, their morphology is attributed to their specific electronic and optical properties, such as increased charge transfer and large polarization anisotropy. They are very good candidates for application in photovoltaics, lighting, and visualization and even for biomedical applications.

Breakthroughs in Photonics 2014: Time-Scale-Dependent Nonlinear Dynamics in InAs/InP Quantum Dot Gain Media: From High-Speed Modulation to Coherent Light–Matter Interactions

The dynamical properties of InP-based quantum dot (QD) gain media are surveyed and analyzed for three time scales ranging from tens of picoseconds to less than 200 fs, where quantum coherent phenomena are observable. Each of these time scales determines the important properties of QD devices, i.e., modulation capabilities, nonlinear gain, and coherent light-matter interactions. Experimental investigations and modeling results are described, highlighting the state of the art in QD devices for the important 1550-nm telecom wavelength range.

Breakthroughs in Photonics 2014: Optical Physical-Layer Network Coding, Recent Developments, and Challenges

Network coding is a revolutionary technique that can enhance network throughput and protection. This paper introduces optical physical-layer network coding (OPNC) and the recent development of OPNC, with focused discussion on “common-channel” OPNC that can efficiently utilize network resources. It also describes the challenges ahead of OPNC, including incorporating more than two signals for OPNC; circumventing the higher signal processing complexity when higher order modulations are adopted; and exploiting OPNC in more sophisticated multichannel systems.

Breakthroughs in Photonics 2014: Phase Change Materials for Photonics

Materials that undergo an electronic phase change in a reversible manner open up new directions for research in light-matter interactions and photonic devices. The highly tunable dielectric properties, along with the spatial control of insulating and metallic domains, create photonic-crystal-like environments to control light propagation. In this brief overview, recent advances in photonics that utilize solid-state phase-change systems such as vanadium dioxide (VO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> ) and chalcogenides are discussed. The controllable optical properties such as the refractive index and the optical conductance between two distinct phases in these materials pave the way for switchable photonic devices with memory. Furthermore, the intermediate states with the coexistence of two phases in the vicinity of phase transition in these materials behave as a tunable metamaterial with extraordinary optical properties that is promising for applications such as perfect absorbers.

Breakthroughs in Photonics 2014: Recent Advances in 3-D Integral Imaging Sensing and Display

Integral imaging concept provides a fascinating tool for the capture and display of 3-D images or movies with full parallax, with no need for special glasses and without visual fatigue due to the convergence and accommodation conflict. The limitations and recent advances in integral imaging are discussed.

Breakthroughs in Photonics 2013

Breakthroughs in Photonics is a Special Issue of the IEEE PHOTONICS JOURNAL that brings a compilation of short reviews describing significant accomplishments in selected areas of Photonics within the last year. Breakthroughs in Photonics 2013 contains 15 invited comprehensive, refereed reviews written by experts that cover progress in the areas of Photon sources from far infrared to X-rays; Photonics materials and engineered photonic structures; Nano-photonics; Biophotonics; Imaging and Visualization; Integrated photonic systems; and Terahertz photonics. Photon sources focus on recent advances in semiconductor lasers, including Raman lasers, modelocked lasers, and electrically pumped semiconductor entangled sources. Photonics materials and engineered photonic structures describes novel optics and engineered nanophotonics structures that are tailored to manipulate light from the infrared to the X-ray. Nanophotonics covers advances in nano-antennas which are promising for applications in sensing and telecommunications, among others. Biophotonics describes schemes that make use of nanoplasmonics for label-free sensing of biological samples. Four reviews in imaging describe the latest advances in holography, Fourier ptycographic imaging, quantitative phase imaging, and photoacoustic tomography and their multiple applications, including biology and biomedicine. Integrated photonic systems presents an overview of the main achievements in feedback-controlled integrated photonics. Terahertz photonics covers recent advances in sources and their applications, in particular in wireless communications that have the potential to achieve 100 Gbits/s.

Breakthroughs in Photonics 2013: THz Communications Based on Photonics

There has been an increasing interest in the application of terahertz (THz) waves to broadband wireless communications. In particular, use of frequencies above 275 GHz is one of the big concerns among radio scientists and engineers, because these frequency bands have not yet been allocated at specific active services, and there is a possibility to employ extremely large bandwidths for ultrabroadband wireless communications. Introduction of photonics technologies for signal generation, modulation, and detection is effective not only to enhance the bandwidth and/or the data rate but also to combine fiber-optic and wireless networks. This paper reviews recent progress in THz wireless communications using telecom-based photonics technologies towards 100 Gb/s.

Breakthroughs in Photonics 2013: Passive Mode-Locking of Quantum-Dot Lasers

Most recent achievements in passive mode-locking of quantum-dot lasers, with the main focus on jitter reduction and frequency tuning, are described. Different techniques, leading to record values for integrated jitter of 121 fs and a locking range of 342 MHz, are presented for a 40-GHz laser. Optical feedback is observed to be the method of choice in this field. For the first time, five different optical-feedback regimes are discovered, including the resonant one yielding a radio-frequency linewidth reduction by 99%.

Breakthroughs in Photonics 2013: Fourier Ptychographic Imaging

Fourier ptychography (FP) is a recently developed computational framework for high-resolution high-throughput imaging. In this paper, we will review the latest development of the Fourier ptychographic imaging scheme. We will demonstrate its applications in wide-field imaging, quantitative phase imaging, and adaptive imaging. We will also discuss its potential applications in X-ray optics and transmission electron microscopy.

Breakthroughs in Photonics 2013: Quantitative Phase Imaging: Metrology Meets Biology

Quantitative phase imaging (QPI) is an emerging optical approach that measures the optical path length of a transparent specimen noninvasively. Therefore, it is suitable for studying unstained biological tissues and cells with high sensitivity and resolution. This capability of QPI has fueled itself to grow rapidly as an active field of study for the past two decades. With this trend, QPI has experienced some breakthroughs in methods and applications in the past year. We briefly review some of these breakthroughs in method, including QPI through silicon marker-free phase nanoscopy and white-light diffraction tomography. Furthermore, some of the applications, such as quantitative phase measurement of cell growth and real-time blood testing, are introduced to show the importance and applicability of the field.

Breakthroughs in Photonics 2013: Electrically Pumped Semiconductor Entangled Sources

Recent advances enabling the realization of room-temperature electrically injected chip sources for entangled photons will be highlighted and discussed. Emphasis will be placed on monolithic and hybrid integration settings that enable room-temperature and self-contained operation through electrical current injection. Compound semiconductors, as well as hybrid integration platforms such as those utilizing Si-on-insulator technology, play a central role in defining the approaches sought to realize these sources.

Breakthroughs in Photonics 2013: Holographic Imaging

Although holography is topic that goes back to the 1950s, the research in this field continues to be very active worldwide. A continuous growth is confirmed by the publication of more than 2000 papers each year in archival journal on different holographic issues. Here we describe shortly what appeared to us to be the most significant achievements reached in 2013 on holographic imaging.

Breakthroughs in Photonics 2013: Toward Feedback-Controlled Integrated Photonics

We present an overview of the main achievements obtained in 2013 on the monitoring, stabilization, and feedback loop control of passive and active photonic integrated circuits. Key advances contributed to the evolution of photonic technologies from the current device level toward complex, adaptive, and reconfigurable integrated circuits.

Breakthroughs in Photonics 2012: Breakthroughs in Microwave Quantum Photonics in Superconducting Circuits

The latest breakthroughs in microwave quantum photonics in superconducting circuits are presented. Advancing technologies of Josephson junction quantum bits (qubits) have been applied to control and measurement of itinerant microwave fields. Methods to generate nonclassical microwave states such as single-photon states and squeezed states have been developed. Techniques to characterize those nonclassical itinerant states have also been established. They are ready to be combined to demonstrate various quantum protocols, which extend the possibilities of quantum information processing, quantum metrology, and quantum communications using superconducting circuits.

Editorial: Breakthroughs in Photonics 2012

Breakthroughs in Photonics is a Special Issue of the IEEE Photonics Journal that brings a compilation of short reviews describing significant accomplishments in selected areas of Photonics within the last year. Breakthroughs in Photonics 2012 contains 14 invited comprehensive, refereed reviews written by experts that cover progress in the areas of Coherent Photon Sources; Photonics materials and engineered photonic structures; Ultrafast, attosecond, high field, and short wavelength photonics; Nano-photonics; Photovoltaics; Biophotonics; Sensors; Imaging and Visualization; Integrated Photonic Systems; and Quantum Computing. The selection of the topics and invited contributions is carried out by the IEEE Photonics Journal Editorial Board. The articles in this focus issue highlight the increasingly dominant role of photonics in unraveling fundamental science and, at the same time, enabling applications in, for example, sensing and visualization, nanofabrication, photovoltaics, fiber optics, and quantum photonics. The adoption of article numbers versus page numbers by the IEEE Photonics Journal in 2013 enables, for the first time, publication of each article from Breakthroughs in Photonics 2012 independently in IEEE Xplore, providing more visibility to authors and enhanced readership.

Breakthroughs in Photonics 2012: Space-Division Multiplexing in Multimode and Multicore Fibers for High-Capacity Optical Communication

We summarize the latest advances in space-division multiplexing (SDM) for increasing the capacity per fiber strand. We discuss SDM fibers, recent SDM transmission experiments, subsystems suitable for SDM systems, as well as integrated components able to manipulate multiple spatial modes within a single optical device.