As community concerns about global energy consumption grow, the power of Internet is becoming an issue increasing importance. In this paper, we present a network-based model in optical IP networks and use to estimate Internet. The includes core, metro edge, access video distribution networks, takes into account switching transmission equipment. We include number technologies, including digital subscriber line with ADSL2+, fiber home using passive node combined very high-speed point-to-point...

Traffic patterns in access networks have evolved from voice- and text-oriented services to video- image-based services. This change will require new that support high-speed (> 100 Mb/s), symmetric, guaranteed bandwidths for future video with high-definition TV quality. To satisfy the required bandwidth over a 20-km transmission distance, single-mode optical fiber is currently only practical choice. minimize cost of implementing an FTTP solution, passive network (PON) uses point-to-multipoint...

Optical interconnects have been recognized as the most promising solution to accelerate data transmission in artificial intelligence era. Benefiting from their cost-effectiveness, compact dimensions, and wavelength multiplexing capability, silicon microring resonator modulators emerge a compelling scalable means for optical modulation. However, inherent trade-off between bandwidth modulation efficiency hinders device performance. Here we demonstrate dense division modulator array on chip...

We review technologies and architectures for WDM optical IP networks from the viewpoint of capital expenditure network energy consumption. show how requirements low cost consumption can influence choice switching as well overall architecture.

Dispersion causes a power penalty at certain fibre distances and frequencies in conventional millimetre-wave intensity modulation. Single sideband optical modulation using Bragg grating eliminates the dispersion-induced over frequency length.

We present a comparison of energy consumption access networks. consider passive optical networks, fiber to the node, point-to-point systems and WiMAX. Optical technologies provide most energy-efficient solutions.

Dielectric high-contrast sub-wavelength grating (SWG) structures have received much attention in recent years, offering a new paradigm for the integration of optical systems. Their nanoscale resonant properties can result complex and unintuitive far-field behavior that, if carefully crafted, allows full control phase front from thin planar layer. To date, experimental demonstrations these devices only been realized with polarized light reflective mode, greatly limiting their use practical In...

Silicon-germanium (Si–Ge)-based avalanche photodiodes (APDs) have shown a significant improvement in receiver sensitivity compared to their III–V counterparts due the superior impact ionization property of silicon. However, conventional Si–Ge APDs typically operate at high voltages and low speed, limiting application this technology data communication. In paper, we present waveguide photodiode using thin silicon multiplication region with breakdown voltage −10  V, speed 25 GHz,...

Efficient and selective coupling between a single-mode fiber the LP(11) mode of double-mode is demonstrated in an evanescent directional coupler. With greater than 90% to mode, suppression coupled power lower-order LP(01) was measured be at least 24 dB. This device has application as modal filter for construction in-line all-fiber optical components.

Silicon-germanium (Si-Ge) avalanche photodiodes (APDs) have large gain bandwidth product (GBP) and low excess noise due to the impact ionization coefficient ratio of silicon. Optical receivers using APDs are able achieve high-speed energy efficient optical transceiver systems. We demonstrate a waveguide Si-Ge APD with breakdown voltage -10V, achieving 60 Gb/s PAM4 successfully. A compact circuit model was constructed allow photonic devices circuitry co-design. The receiver has achieved -16...

A compact two-segment depletion mode silicon microring resonator modulator with PAM4 modulation data rate up to 100 Gb/s has been demonstrated. The exhibits a free spectrum range of ∼5.7 nm, quality factor ∼3600, DC extinction ratio ∼13 dB, an electro-optical phase shift efficiency Vπ·L ∼1 V·cm, and bandwidth ∼40 GHz.

An analysis of coherent optical FMCW is presented. It shows the limitations imposed on measurements discrete reflections and Rayleigh backscattering due to phase noise originating in finite coherence length source. The dependence range for accurate particular parameters system discussed general case three specific laser sources.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

It is shown that by attenuating the reference power in an optical low-coherence reflectometry (OLCR) measurement, reflection sensitivity can be improved, even though, many other types of measurements, improved as increased. The difference due to presence inherent intensity noise associated with sources, which dominate over shot at powers are low 1 mu W. A -146 dB demonstrated using this technique.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML"...

A general rigorous theory of optical heterodyne and homodyne measurements is presented. The power spectrum the photocurrent resulting from two uncorrelated beams mixing on a photodetector derived. In particular, analysis presented for delayed self-homodyne method which used to characterize laser source linewidth by Mach-Zehnder interferometer with delay exceeding coherence length. Existing treatments are generalized address non-Lorentzian sources arbitrary lineshape. further cover case...

Single-mode fibre recirculating delay lines have been made on a single continuous loop of with the use directional couplers. These devices demonstrated as bandpass filters and notch at centre frequencies from 0.5 MHz to 1.3 GHz depth over 45 dB.

We report an all-Si microring (MRR) avalanche photodiode (APD) with ultrahigh responsivity (R) of 65 A/W, dark current 6.5 µA, and record gain-bandwidth product (GBP) 798 GHz at -7.36 V. The mechanisms for the high have been modelled investigated. Furthermore, open eye diagrams up to 20 Gb/s are supported 1310 nm device is first, best our knowledge, low cost APD that has potential compete commercial Ge- III-V-based photodetectors (PDs). This shows make a standard "black-box" component in Si...

Measurement of optical phase and frequency deviations using a frequency-domain network analysis approach is described. The domain transfer functions are given which relate the conversion phase, frequency, intensity modulation into photodetector current after passing through quadrature biased Mach-Zehnder interferometer. It shown that error term in depends only to second order on any accompanying modulation. Experimental data illustrating analytical results.< <ETX...

A long-coherence-length, diode-pumped, monolithic Nd:YAG laser operating at 1.32 mu m is used to perform coherent FMCW (frequency-modulated continuous wave) reflectometry measurements. Compared with semiconductor-based lasers, the low phase noise of source offers greatly increased distance range combined sensitivity optical reflections. Measurement Rayleigh backscatter from 50 km fiber demonstrated over 60 dB two-way dynamic range. Two-point spatial resolution be better than 10 cm. This and...

A model of energy consumption in IP networks is used to estimate the public Internet. Today's Internet uses less than 1% available electricity supply. However, network could grow substantially as access rates increase.

We propose and demonstrate a novel fiber link loss monitoring method for wavelength-division-multiplexed (WDM) passive optical network. This is based on the signal comparison between reference amplified spontaneous emission its reflection from an reflector. Therefore, we can calculate exactly also measure characteristics of upstream signals without suspending in-service channels. Since this scheme does not use narrow-band wavelength-dependent components such as Bragg gratings, it...

We demonstrate, for the first time, post-growth wavelength setting of electrically-injected vertical-cavity surface-emitting lasers (VCSELs) by using high-contrast gratings (HCGs) with different grating parameters. By fabricating HCGs duty cycle and period, HCG reflection phase can be varied, in effect giving optical cavity lengths HCG-VCSELs This enables fabrication monolithic multi-wavelength HCG-VCSEL arrays wavelength-division multiplexing (WDM). The GaAs is suspended air removing a...

We investigate the use of a 1060 nm single-mode vertical-cavity surface-emitting laser (VCSEL) and fiber as competitive technology for cost- power-efficient long-reach optical interconnects. Error-free transmission (bit error rate <; 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-12</sup> ) over 2 km is demonstrated at bitrates up to 40 Gb/s under on-off keying non-return-to-zero (OOK-NRZ) modulation, without equalization, forward-error...

We present a loop reflector-assisted silicon-germanium waveguide avalanche photodiode with improved responsivity. Compared to the same APD without reflector, it has 1.49 times higher responsivity, ~ 1.12 A/W, compromising speed performance. It exhibits 3 dB-bandwidth of 25 GHz, build-up time limited gain-bandwidth product 296 highest 497 GHz. Clear eye diagrams are measured at both 32 Gbps NRZ and 64 PAM4 modulation, 1 2 dB better sensitivity up -15.7 dBm BER 2.4 ×10 <sup...

Abstract Over the past few years, extensive work on optical neural networks has been investigated in hopes of achieving orders magnitude improvement energy efficiency and compute density via all-optical matrix-vector multiplication. However, these solutions are limited by a lack high-speed power power-efficient phase tuners, on-chip non-volatile memory, proper material platform that can heterogeneously integrate all necessary components needed onto single chip. We address issues...