Showing papers in "Nature Photonics in 2010"
TL;DR: Graphene has high mobility and optical transparency, in addition to flexibility, robustness and environmental stability as discussed by the authors, and its true potential lies in photonics and optoelectronics, where the combination of its unique optical and electronic properties can be fully exploited, even in the absence of a bandgap, and the linear dispersion of the Dirac electrons enables ultrawideband tunability.
Abstract: The richness of optical and electronic properties of graphene attracts enormous interest. Graphene has high mobility and optical transparency, in addition to flexibility, robustness and environmental stability. So far, the main focus has been on fundamental physics and electronic devices. However, we believe its true potential lies in photonics and optoelectronics, where the combination of its unique optical and electronic properties can be fully exploited, even in the absence of a bandgap, and the linear dispersion of the Dirac electrons enables ultrawideband tunability. The rise of graphene in photonics and optoelectronics is shown by several recent results, ranging from solar cells and light-emitting devices to touch screens, photodetectors and ultrafast lasers. Here we review the state-of-the-art in this emerging field.
6,863 citations
TL;DR: In this article, the authors summarized the basic principles and major achievements of plasmon guiding, and details the current state-of-the-art in subwavelength PLASmonic waveguides, passive and active nanoplasmonic components for the generation, manipulation and detection of radiation, and configurations for the nanofocusing of light.
Abstract: Recent years have seen a rapid expansion of research into nanophotonics based on surface plasmon–polaritons. These electromagnetic waves propagate along metal–dielectric interfaces and can be guided by metallic nanostructures beyond the diffraction limit. This remarkable capability has unique prospects for the design of highly integrated photonic signal-processing systems, nanoresolution optical imaging techniques and sensors. This Review summarizes the basic principles and major achievements of plasmon guiding, and details the current state-of-the-art in subwavelength plasmonic waveguides, passive and active nanoplasmonic components for the generation, manipulation and detection of radiation, and configurations for the nanofocusing of light. Potential future developments and applications of nanophotonic devices and circuits are also discussed, such as in optical signals processing, nanoscale optical devices and near-field microscopy with nanoscale resolution.
3,481 citations
TL;DR: The Linac Coherent Light Source free-electron laser has achieved coherent X-ray generation down to a wavelength of 1.2 A and at a brightness that is nearly ten orders of magnitude higher than conventional synchrotrons.
Abstract: The Linac Coherent Light Source free-electron laser has now achieved coherent X-ray generation down to a wavelength of 1.2 A and at a brightness that is nearly ten orders of magnitude higher than conventional synchrotrons. Researchers detail the first operation and beam characteristics of the system, which give hope for imaging at atomic spatial and temporal scales.
2,648 citations
IBM1
TL;DR: In this paper, an asymmetric metallization scheme is adopted to break the mirror symmetry of the internal electric-field profile in conventional graphene field effect transistor channels, allowing for efficient photodetection.
Abstract: Although silicon has dominated solid-state electronics for more than four decades, a variety of other materials are used in photonic devices to expand the wavelength range of operation and improve performance. For example, gallium-nitride based materials enable light emission at blue and ultraviolet wavelengths1, and high index contrast silicon-on-insulator facilitates ultradense photonic devices2,3. Here, we report the first use of a photodetector based on graphene4,5, a two-dimensional carbon material, in a 10 Gbit s−1 optical data link. In this interdigitated metal–graphene–metal photodetector, an asymmetric metallization scheme is adopted to break the mirror symmetry of the internal electric-field profile in conventional graphene field-effect transistor channels6,7,8,9, allowing for efficient photodetection. A maximum external photoresponsivity of 6.1 mA W−1 is achieved at a wavelength of 1.55 µm. Owing to the unique band structure of graphene10,11 and extensive developments in graphene electronics12,13 and wafer-scale synthesis13, graphene-based integrated electronic–photonic circuits with an operational wavelength range spanning 300 nm to 6 µm (and possibly beyond) can be expected in the future. A graphene-based photodetector with unprecedented photoresponsivity and the ability to perform error-free detection of 10 Gbit s−1s data streams is demonstrated. The results suggest that graphene-based photonic devices have a bright future in telecommunications and other optical applications.
2,238 citations
TL;DR: The techniques that have, and will, be used to implement silicon optical modulators, as well as the outlook for these devices, and the candidate solutions of the future are discussed.
Abstract: Optical technology is poised to revolutionize short-reach interconnects. The leading candidate technology is silicon photonics, and the workhorse of such an interconnect is the optical modulator. Modulators have been improved dramatically in recent years, with a notable increase in bandwidth from the megahertz to the multigigahertz regime in just over half a decade. However, the demands of optical interconnects are significant, and many questions remain unanswered as to whether silicon can meet the required performance metrics. Minimizing metrics such as the device footprint and energy requirement per bit, while also maximizing bandwidth and modulation depth, is non-trivial. All of this must be achieved within an acceptable thermal tolerance and optical spectral width using CMOS-compatible fabrication processes. This Review discusses the techniques that have been (and will continue to be) used to implement silicon optical modulators, as well as providing an outlook for these devices and the candidate solutions of the future.
2,110 citations
TL;DR: In this article, the authors proposed a method to extend group IV photonics from near-infrared to midinfrared wavelengths using on-chip CMOS optoelectronic systems for use in spectroscopy, chemical and biological sensing, and free space communications.
Abstract: Ingenious techniques are needed to extend group IV photonics from near-infrared to mid-infrared wavelengths. If achieved, the reward could be on-chip CMOS optoelectronic systems for use in spectroscopy, chemical and biological sensing, and free-space communications.
1,272 citations
TL;DR: In this article, the authors summarized the major developments in Ge-on-Si photodetectors, including epitaxial growth and strain engineering, free-space and waveguide-integrated devices, as well as recent progress in Geon-On-Si avalanche photodets.
Abstract: The past decade has seen rapid progress in research into high-performance Ge-on-Si photodetectors. Owing to their excellent optoelectronic properties, which include high responsivity from visible to near-infrared wavelengths, high bandwidths and compatibility with silicon complementary metal–oxide–semiconductor circuits, these devices can be monolithically integrated with silicon-based read-out circuits for applications such as high-performance photonic data links and infrared imaging at low cost and low power consumption. This Review summarizes the major developments in Ge-on-Si photodetectors, including epitaxial growth and strain engineering, free-space and waveguide-integrated devices, as well as recent progress in Ge-on-Si avalanche photodetectors. Owing to their excellent optoelectronic properties, Ge-on-Si photodetector can be monolithically integrated with silicon-based read-out circuits for applications such as high-performance photonic data links and low-cost infrared imaging at low power consumption. This Review covers the major developments in Ge-on-Si photodetectors, including epitaxial growth and strain engineering, free-space and waveguide-integrated devices, as well as recent progress in Ge-on-Si avalanche photodetectors.
1,259 citations
TL;DR: In this article, a review of nonlinear effects in silicon and highlights the important applications and technological solutions in nonlinear silicon photonics is presented. But the authors do not discuss the nonlinearities in silicon.
Abstract: The nonlinearities in silicon are diverse. This Review covers the wealth of nonlinear effects in silicon and highlights the important applications and technological solutions in nonlinear silicon photonics. The increasing capability for manufacturing a wide variety of optoelectronic devices from polymer and polymer–silicon hybrids, including transmission fibre, modulators, detectors and light sources, suggests that organic photonics has a promising future in communications and other applications.
1,123 citations
TL;DR: In this article, the authors report real-time detection and sizing of single nanoparticles, down to 30 nm in radius, using mode splitting in a monolithic ultrahigh-quality-factor (Q) whispering-gallery-mode microresonator.
Abstract: The ability to detect and size individual nanoparticles with high resolution is crucial to understanding the behaviour of single particles and effectively using their strong size-dependent properties to develop innovative products. We report realtime, in situ detection and sizing of single nanoparticles, down to 30 nm in radius, using mode splitting in a monolithic ultrahigh-quality-factor (Q) whispering-gallery-mode microresonator. Particle binding splits a whispering-gallery mode into two spectrally shifted resonance modes, forming a self-referenced detection scheme. This technique provides superior noise suppression and enables the extraction of accurate particle size information with a single-shot measurement in a microscale device. Our method requires neither labelling of the particles nor a priori information on their presence in the medium, providing an effective platform to study nanoparticles at single-particle resolution. With the rapid progress in nanotechnology, nanoparticles of different materials and sizes have been synthesized and engineered as key components in various applications ranging from solar cell
1,068 citations
TL;DR: In this paper, the authors demonstrate the first monolithically integrated CMOS-compatible source by creating an optical parametric oscillator formed by a silicon nitride ring resonator on silicon.
Abstract: Silicon photonics enables the fabrication of on-chip, ultrahigh-bandwidth optical networks that are critical for the future of microelectronics1,2,3 Several optical components necessary for implementing a wavelength division multiplexing network have been demonstrated in silicon However, a fully integrated multiple-wavelength source capable of driving such a network has not yet been realized Optical amplification, a necessary component for lasing, has been achieved on-chip through stimulated Raman scattering4,5, parametric mixing6 and by silicon nanocrystals7 or nanopatterned silicon8 Losses in most of these structures have prevented oscillation Raman oscillators have been demonstrated9,10,11, but with a narrow gain bandwidth that is insufficient for wavelength division multiplexing Here, we demonstrate the first monolithically integrated CMOS-compatible source by creating an optical parametric oscillator formed by a silicon nitride ring resonator on silicon The device can generate more than 100 new wavelengths with operating powers below 50 mW This source can form the backbone of a high-bandwidth optical network on a microelectronic chip A monolithically integrated CMOS-compatible source is demonstrated using an optical parametric oscillator based on a silicon nitride ring resonator on silicon Generating more than 100 wavelengths simultaneously and operating at powers below 50 mW, scientists say that it may form the basis of an on-chip high-bandwidth optical network
1,052 citations
TL;DR: In this paper, the authors review the most recent progress in this field, including low-threshold silicon Raman lasers with racetrack ring resonator cavities, the first germanium-on-silicon lasers operating at room temperature, and hybrid silicon microring and microdisk lasers.
Abstract: Silicon lasers have long been a goal for semiconductor scientists, and a number of important breakthroughs in the past decade have focused attention on silicon as a photonic platform. Here we review the most recent progress in this field, including low-threshold silicon Raman lasers with racetrack ring resonator cavities, the first germanium-on-silicon lasers operating at room temperature, and hybrid silicon microring and microdisk lasers. The fundamentals of carrier transition physics in crystalline silicon are discussed briefly. The basics of several important approaches for creating lasers on silicon are explained, and the challenges and opportunities associated with these approaches are discussed. Silicon lasers have long been a goal for semiconductor scientists. This Progress Article reviews the most recent developments in this field, including silicon Raman lasers, the first germanium-on-silicon lasers operating at room temperature, and hybrid silicon microring and microdisk lasers. Challenges and opportunities for the present approaches are also discussed.
TL;DR: By using bright pulses of light to ‘blind’ the avalanche photodiode detectors used in quantum cryptography equipment, scientists in Europe have shown that it is possible to tracelessly steal the secret encryption key generated by such systems and thus compromise their security.
Abstract: By using bright pulses of light to ‘blind’ the avalanche photodiode detectors used in quantum cryptography equipment, scientists in Europe have shown that it is possible to tracelessly steal the secret encryption key generated by such systems and thus compromise their security.
TL;DR: In this paper, an InAs quantum dot embedded in a GaAs photonic nanowire with carefully tailored ends was used to achieve a record source efficiency of 0.72, combined with pure single-photon emission.
Abstract: The development of efficient solid-state sources of single photons is a major challenge in the context of quantum communication, optical quantum information processing and metrology. Such a source must enable the implementation of a stable, single-photon emitter, like a colour centre in diamond or a semiconductor quantum dot. Achieving a high extraction efficiency has long been recognized as a major issue, and both classical solutions and cavity quantum electrodynamics effects have been applied. We adopt a different approach, based on an InAs quantum dot embedded in a GaAs photonic nanowire with carefully tailored ends. Under optical pumping, we demonstrate a record source efficiency of 0.72, combined with pure single-photon emission. This non-resonant approach also provides broadband spontaneous emission control, thus offering appealing novel opportunities for the development of single-photon sources based on spectrally broad emitters, wavelength-tunable sources or efficient sources of entangled photon pairs.
TL;DR: Polariton lasing at room temperature in an organic microcavity composed of a melt-grown anthracene single crystal sandwiched between two dielectric mirrors is reported in this paper.
Abstract: The optical properties of organic semiconductors are almost exclusively described using the Frenkel exciton picture1. In this description, the strong Coulombic interaction between an excited electron and the charged vacancy it leaves behind (a hole) is automatically taken into account. If, in an optical microcavity, the exciton–photon interaction is strong compared to the excitonic and photonic decay rates, a second quasiparticle, the microcavity polariton, must be introduced to properly account for this coupling2. Coherent, laser-like emission from polaritons has been predicted to occur when the ground-state occupancy of polaritons 〈ngs〉, reaches 1 (ref. 3). This process, known as polariton lasing, can occur at thresholds much lower than required for conventional lasing. Polaritons in organic semiconductors are highly stable at room temperature, but to our knowledge, there has as yet been no report of nonlinear emission from these structures. Here, we demonstrate polariton lasing at room temperature in an organic microcavity composed of a melt-grown anthracene single crystal sandwiched between two dielectric mirrors. Polaritons in organic semiconductors are highly stable at room temperature, but so far nonlinear emission from these structures has not been demonstrated. Here, polariton lasing at room temperature in an organic microcavity composed of a melt-grown anthracene single crystal sandwiched between two dielectric mirrors is reported.
TL;DR: In this article, the authors used spatial wavefront shaping to improve the focusing resolution of a lens by using wave front shaping to compensate for scattering in an inhomogeneous medium between the lens and the focal plane.
Abstract: Optical microscopy and manipulation methods rely on the ability to focus light to a small volume. However, in inhomogeneous media such as biological tissue, light is scattered out of the focusing beam. Disordered scattering is thought to fundamentally limit the resolution and penetration depth of optical methods1,2,3. Here we demonstrate, in an optical experiment, that scattering can be used to improve, rather than deteriorate, the sharpness of the focus. The resulting focus is even sharper than that in a transparent medium. By using scattering in the medium behind a lens, light was focused to a spot ten times smaller than the diffraction limit of that lens. Our method is the optical equivalent of highly successful methods for improving the resolution and communication bandwidth of ultrasound, radio waves and microwaves4,5,6. Our results, obtained using spatial wavefront shaping, apply to all coherent methods for focusing through scattering matter, including phase conjugation7 and time-reversal4. Light is scattered out of a focusing beam when an inhomogeneous medium is placed between the lens and the focal plane. Now, scientists experimentally demonstrate that scattering can be exploited to improve, rather than deteriorate, the focusing resolution of a lens by using wavefront shaping to compensate for scattering.
TL;DR: In this article, a fully integrated, CMOS-compatible, multiple-wavelength source with high differential slope efficiency at only a few tens of milliwatts of continuous-wave power is presented.
Abstract: Integrated multiple-wavelength laser sources, critical for important applications such as high-precision broadband sensing and spectroscopy1, molecular fingerprinting2, optical clocks3 and attosecond physics4, have recently been demonstrated in silica and single-crystal microtoroid resonators using parametric gain2,5,6. However, for applications in telecommunications7 and optical interconnects8, analogous devices compatible with a fully integrated platform9 do not yet exist. Here, we report a fully integrated, CMOS-compatible, multiple-wavelength source. We achieve optical ‘hyper-parametric’ oscillation in a high-index silica-glass microring resonator10 with a differential slope efficiency above threshold of 7.4% for a single oscillating mode, a continuous-wave threshold power as low as 54 mW, and a controllable range of frequency spacing from 200 GHz to more than 6 THz. The low loss, design flexibility and CMOS compatibility of this device will enable the creation of multiple-wavelength sources for telecommunications, computing, sensing, metrology and other areas. Through optical ‘hyper-parametric’ oscillation in a high-index silica glass microring resonator, scientists demonstrate a fully integrated CMOS-compatible low-loss multiple-wavelength source that has high differential slope efficiency at only a few tens of milliwatts of continuous-wave power. The achievement has significant implications for telecommunications and on-chip optical interconnects in computers.
TL;DR: The increasing capability for manufacturing a wide variety of optoelectronic devices from polymer and polymer-silicon hybrids, including transmission fibre, modulators, detectors and light sources, suggests that organic photonics has a promising future in communications and other applications.
Abstract: The increasing capability for manufacturing a wide variety of optoelectronic devices from polymer and polymer–silicon hybrids, including transmission fibre, modulators, detectors and light sources, suggests that organic photonics has a promising future in communications and other applications.
TL;DR: In this paper, the authors reported the first experimental observation of temporal cavity solitons, which are packets of light persisting in a continuously driven nonlinear resonator and are used to demonstrate storage of a data stream for more than a second.
Abstract: Temporal cavity solitons are packets of light persisting in a continuously driven nonlinear resonator. They are robust attracting states, readily excited through a phase-insensitive and wavelength-insensitive process. As such, they constitute an ideal support for bits in an optical buffer that would seamlessly combine three critical telecommunication functions, namely all-optical storage, all-optical reshaping and wavelength conversion. Here, with standard silica optical fibres, we report the first experimental observation of temporal cavity solitons. The cavity solitons are 4 ps long and are used to demonstrate storage of a data stream for more than a second. We also observe interactions of close cavity solitons, revealing for our set-up a potential capacity of up to 45,000 bits at 25 Gbit s−1. More fundamentally, cavity solitons are localized dissipative structures. Therefore, given that silica exhibits a pure instantaneous Kerr nonlinearity, our experiment constitutes one of the simplest examples of self-organization phenomena in nonlinear optics. Using standard silica optical fibres, scientists observe temporal cavity solitons — packets of light persisting in a continuously driven nonlinear resonator. Cavity solitons 4 ps long are reported and used to demonstrate storage of a data stream for more than a second. The findings represent one of the simplest examples of self-organization phenomena in nonlinear optics.
TL;DR: In this article, a combination of an ultrasmall photonic-crystal nanocavity and strong carrier-induced nonlinearity in InGaAsP was used to demonstrate low-energy switching within a few tens of picoseconds.
Abstract: Although high-speed all-optical switches are expected to replace their electrical counterparts in information processing, their relatively large size and power consumption have remained obstacles. We use a combination of an ultrasmall photonic-crystal nanocavity and strong carrier-induced nonlinearity in InGaAsP to successfully demonstrate low-energy switching within a few tens of picoseconds. Switching energies with a contrast of 3 and 10 dB of 0.42 and 0.66 fJ, respectively, have been obtained, which are over two orders of magnitude lower than those of previously reported all-optical switches. The ultrasmall cavity substantially enhances the nonlinearity as well as the recovery speed, and the switching efficiency is maximized by a combination of two-photon absorption and linear absorption in the InGaAsP nanocavities. These switches, with their chip-scale integratability, may lead to the possibility of low-power, high-density, all-optical processing in a chip. All-optical switching energies as small as 0.42 fJ — two orders of magnitude lower than previously reported — are demonstrated in small photonic crystal cavities incorporating InGaAsP. These devices can switch within a few tens of picoseconds, and may therefore have potential for low-power high-density all-optical processing on a chip.
TL;DR: In this paper, the authors describe how X-ray free-electron lasers work, discuss the range of new sources being developed worldwide, and consider how such Xray sources may develop over the coming years.
Abstract: With intensities 108–1010 times greater than other laboratory sources, X-ray free-electron lasers are currently opening up new frontiers across many areas of science. In this Review we describe how these unconventional lasers work, discuss the range of new sources being developed worldwide, and consider how such X-ray sources may develop over the coming years.
TL;DR: In this article, the scientific origins of the technology of liquid-crystal laser and reviews the current cutting-edge research are discussed. But the focus of this paper is on the current state of the art.
Abstract: Wide-band tunability, large coherence-area, and in some cases multidirectional emission have made liquid-crystal lasers an attractive light source for applications like miniature medical diagnostic tool and large-area holographic laser displays. This article discusses the scientific origins of the technology of liquid-crystal lasers and reviews the current cutting-edge research.
TL;DR: In this paper, a sub-shot-noise imaging using spatial quantum correlations between parametric down-conversion light beams is demonstrated, which exhibits a larger signal-tonoise ratio than is possible through classical imaging methods.
Abstract: Sub-shot-noise imaging using spatial quantum correlations between parametric down-conversion light beams is demonstrated. The scheme exhibits a larger signal-to-noise ratio than is possible through classical imaging methods.
TL;DR: In this paper, a Yagi-Uda directional antenna was demonstrated at visible wavelengths using an array of appropriately tuned nanoparticles to replicate the reflecting and directing elements of the original design.
Abstract: A Yagi–Uda directional antenna — the work horse of radiofrequency communications for more than 60 years — has now been demonstrated at visible wavelengths An array of appropriately tuned nanoparticles replicate the reflecting and directing elements of the original design Directional control of radiation from the nano-optical Yagi–Uda antenna was experimentally shown
TL;DR: In this paper, a self-reconstructing Bessel beam was used to reduce scattering artifacts and increase image quality and penetration depth in three-dimensional inhomogeneous opaque media.
Abstract: A prototype microscope built with self-reconstructing Bessel beams is shown to be able to reduce scattering artifacts as well as increase image quality and penetration depth in three-dimensional inhomogeneous opaque media.
TL;DR: In this paper, the first observation of a class of versatile three-dimensional linear light "bullets" was reported, where Bessel beams in the transverse plane with temporal Airy pulses were used to generate spatiotemporal optical wave packets resistant to both dispersion and diffraction.
Abstract: The generation of spatiotemporal optical wave packets that are resistant to both dispersion and diffraction are attractive for bioimaging applications and plasma physics. By combining Bessel beams in the transverse plane with temporal Airy pulses, scientists now report the first observation of a class of versatile three-dimensional linear light ‘bullets’.
TL;DR: A review of recent work in the development of direct image-forming X-ray microscopy techniques and the relevant applications can be found in this article, including three-dimensional biological tomography, dynamical processes in magnetic nanostructures, chemical speciation studies, industrial applications related to solar cells and batteries, and studies of archaeological materials.
Abstract: Recent years have seen significant progress in the field of soft- and hard-X-ray microscopy, both technically, through developments in source, optics and imaging methodologies, and also scientifically, through a wide range of applications While an ever-growing community is pursuing the extensive applications of today's available X-ray tools, other groups are investigating improvements in techniques, including new optics, higher spatial resolutions, brighter compact sources and shorter-duration X-ray pulses This Review covers recent work in the development of direct image-forming X-ray microscopy techniques and the relevant applications, including three-dimensional biological tomography, dynamical processes in magnetic nanostructures, chemical speciation studies, industrial applications related to solar cells and batteries, and studies of archaeological materials and historical works of art
TL;DR: In this paper, a non-periodic pattern of the grating surface is proposed to give full control over the phase front of reflected light while maintaining a high reflectivity, which could have a substantial impact on a number of applications that depend on low-cost, compact optical components.
Abstract: Sub-wavelength dielectric gratings have emerged recently as a promising alternative to distributed Bragg reflection dielectric stacks for broadband, high-reflectivity filtering applications. Such a grating structure composed of a single dielectric layer with the appropriate patterning can sometimes perform as well as 30 or 40 dielectric distributed Bragg reflection layers, while providing new functionalities such as polarization control and near-field amplification. In this Letter, we introduce an interesting property of grating mirrors that cannot be realized by their distributed Bragg reflection counterpart: we show that a non-periodic patterning of the grating surface can give full control over the phase front of reflected light while maintaining a high reflectivity. This new feature of dielectric gratings allows the creation of miniature planar focusing elements that could have a substantial impact on a number of applications that depend on low-cost, compact optical components, from laser cavities to CD/DVD read/write heads.
TL;DR: In this paper, an organic light-emitting diodes featuring layers with a spontaneously formed buckled geometry are demonstrated to offer at least a twofold improvement in light extraction efficiency across the entire visible spectrum.
Abstract: Organic light-emitting diodes featuring layers with a spontaneously formed buckled geometry are demonstrated to offer at least a twofold improvement in light extraction efficiency across the entire visible spectrum.
TL;DR: A high-definition LIDAR system with a rotating sensor head containing 64 semiconductor lasers allows the efficient generation of 3D environment maps at unprecedented levels of detail.
Abstract: A high-definition LIDAR system with a rotating sensor head containing 64 semiconductor lasers allows the efficient generation of 3D environment maps at unprecedented levels of detail.
TL;DR: The development of the first practical ('black-box') all-optical regenerator capable of removing both phase and amplitude noise from binary phase-encoded optical communications signals is reported.
Abstract: Fibre-optic communications systems have traditionally carried data using binary (on-off) encoding of the light amplitude. However, next-generation systems will use both the amplitude and phase of the optical carrier to achieve higher spectral efficiencies and thus higher overall data capacities(1,2). Although this approach requires highly complex transmitters and receivers, the increased capacity and many further practical benefits that accrue from a full knowledge of the amplitude and phase of the optical field(3) more than outweigh this additional hardware complexity and can greatly simplify optical network design. However, use of the complex optical field gives rise to a new dominant limitation to system performance-nonlinear phase noise(4,5). Developing a device to remove this noise is therefore of great technical importance. Here, we report the development of the first practical ('black-box') all-optical regenerator capable of removing both phase and amplitude noise from binary phase-encoded optical communications signals.