Gatti D.,CNR Institute for Photonics and Nanotechnologies |
Gotti R.,CNR Institute for Photonics and Nanotechnologies |
Sala T.,CNR Institute for Photonics and Nanotechnologies |
Coluccelli N.,CNR Institute for Photonics and Nanotechnologies |
And 3 more authors.
Optics Letters | Year: 2015
An integrated single-sideband modulator is used as the sole wide-bandwidth frequency actuator in a Pound-Drever-Hall locking loop. Thanks to the large modulation bandwidth, the device enables a locking range of ±75 MHz and a control bandwidth of 5 MHz without the need for a second feedback loop. As applied to the coupling of an extended-cavity diode laser at 1.55 μm to a high-finesse optical cavity, the in-loop frequency noise spectral density reaches a minimum of 1 mHz/Hz1/2 at 1 kHz. © 2015 Optical Society of America.
Dahdah N.E.,University of Swansea |
Dahdah N.E.,Stanford University |
Govan D.S.,Oclaro Inc. |
Jamshidifar M.,University of Swansea |
And 2 more authors.
IEEE Journal on Selected Topics in Quantum Electronics | Year: 2012
We have reduced signal-signal four-wave mixing crosstalk in a fiber optical parametric amplifier (OPA) by using a short nonlinear fiber for the gain medium and a high-power pump. This allowed us to obtain less than 1 dB penalty for amplification of 26 dense wavelength-division multiplexed (WDM) channels modulated at 43.7Gb/s return to zero-differential phase-shift keying, with the OPA placed between transmitter and receiver. We then used the same OPA in several different roles for a long-haul transmission system. We did not insert the OPA within the loop, but investigated this role indirectly by using equivalent results for small numbers of loop recirculations. We found that standard erbium-doped fiber amplifiers currently hold an advantage over this OPA, which becomes negligible for long distances. This paper shows that at this time OPAs can handle amplification of WDM traffic in excess of 1 Tb/s with little degradation. It also indicates that with further improvements, fiber OPAs could be a contender for wideband amplification in future optical communication networks. © 2011 IEEE.
News Article | November 18, 2016
Transceiver is a device that performs both transmission and reception of signals with a common circuitry over a network. An optical transceiver, also called as fiber optic transmitter and receiver, completes the operation of transmission by converting the electrical signal in light pulse and vice versa at the receiving end. In case of fiber optics, the information is sent in the form of light pulses. The light pulses need to be converted into electrical signals in order to be used by an electronic device. This photoelectric conversion is carried by the optical module equipped at the end terminals of the network. The light from the end of connecting cable is coupled to the receiver, where a detector carries the conversion of the light signal back into an equivalent electrical signal. A laser diode or a light emitting diode (LED) is used as the light source for transmission of information. There are numerous optical transceiver modules available in the market differing in the type of data transmission speed, connections and packing forms. Some of the types of optical transceivers available in the market include SFP, SFP+, X2, XFP, Xenpak, GBIC and others. Furthermore, as per the type of connection, there are single mode (SM), multi-mode (MM) and Wavelength Division Multiplexing (WDM) modules. Optical transceivers are the modernized components for the efficient use of network. The major factor bolstering the adoption of optical transceiver components is their low cost transport of information over the network. Additionally, optical transceivers are preferred over conventional transceiver devices as they require low maintenance cost as compared to conventional devices. Optical transceivers support large bandwidth and hence, are widely used in high speed network infrastructure such as broadband internet connections. These are used as both carriers and data centers. Optical transceivers are deployed to update the communication networks and data center networks for efficient traffic management with higher speeds. Optical networks are the backbone for mobile communication network. With growing demand for reliable and high speed mobile communication, optical transceivers are increasingly being used for the communication network infrastructure. Geographically, North America is seen as highly attractive market for the optical transceivers due to increasing demand for sophisticated communication network. In addition, the rising deployment of 100G transceivers for high speed networks is another factor contributing to high demand for optical transceivers. Europe is equally fast in adoption of 100G transceivers and follows North America in terms of demand for optical transceivers. Moreover, the combined use of 40G and 100G modules in Europe and North America is expected to show steady growth in demand for optical transceivers in near future. In Asia-Pacific, China is expected to be the fastest growing market for optical transceivers owing to its increasing demand for deployment of 100G equipment. The updating of the existing communication networks in this region is another factor which is expected to boost the growth of optical transceivers market in near future. In North America, JDS Uniphase Corporation, Oclaro Inc., Finisar Corporation, Cisco Systems, Alcatel-Lucent and others are the manufacturers of optical transceivers. In Asia-Pacific, Avago Technologies and Wuhan Telecommunications Devices Co. Ltd. are some of the leading manufacturers of optical transceivers.
PubMed | Oclaro Inc., Polytechnic of Milan and CNR Institute for Photonics and Nanotechnologies
Type: | Journal: Scientific reports | Year: 2016
Overcoming the Doppler broadening limit is a cornerstone of precision spectroscopy. Nevertheless, the achievement of a Doppler-free regime is severely hampered by the need of high field intensities to saturate absorption transitions and of a high signal-to-noise ratio to detect tiny Lamb-dip features. Here we present a novel comb-assisted spectrometer ensuring over a broad range from 1.5 to 1.63m intra-cavity field enhancement up to 1.5kW/cm(2), which is suitable for saturation of transitions with extremely weak electric dipole moments. Referencing to an optical frequency comb allows the spectrometer to operate with kHz-level frequency accuracy, while an extremely tight locking of the probe laser to the enhancement cavity enables a 10(-11) cm(-1) absorption sensitivity to be reached over 200s in a purely dc direct-detection-mode at the cavity output. The particularly simple and robust detection and operating scheme, together with the wide tunability available, makes the system suitable to explore thousands of lines of several molecules never observed so far in a Doppler-free regime. As a demonstration, Lamb-dip spectroscopy is performed on the P(15) line of the 01120-00000 band of acetylene, featuring a line-strength below 10(-23)cm/mol and an Einstein coefficient of 5mHz, among the weakest ever observed.
Sharma M.,Oclaro Inc. |
Hansen P.,Oclaro Inc. |
Nayar B.,Oclaro Inc. |
Wigley P.,Oclaro Inc.
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2012
Network operators are moving towards next-generation Colorless, Directionless and Contentionless ROADMs (CDC-ROADMs) to increase the flexibility of their networks. Such so-called CDC-ROADMs require advances in optical component technologies, including high-port count Wavelength Selective Switches, Multicast Switches, Arrayed Amplifiers and Optical Channel Monitors. In this paper, we begin by examining the network-level requirements and see how these translate into component requirements and also identify opportunities to improve how these functional modules are integrated to optimize overall equipment design. © 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).
Chandrasekhar S.,Alcatel - Lucent |
Liu X.,Alcatel - Lucent |
Winzer P.J.,Alcatel - Lucent |
Simsarian J.E.,Alcatel - Lucent |
Griffin R.A.,Oclaro Inc.
National Fiber Optic Engineers Conference, NFOEC 2013 | Year: 2013
We demonstrate, using a compact InP-based integrated assembly of a tunable laser and a double-nested Mach-Zehnder modulator, generation of Nyquist-prefiltered QPSK and 16-QAM signals at 32-Gbaud. We transmitted them over 8000-km and 960-km SSMF, respectively. © 2013 OSA.
Zhu J.,University of Cambridge |
Wonfor A.,University of Cambridge |
Lee S.H.,University of Cambridge |
Pachnicke S.,ADVA Optical Networking |
And 6 more authors.
Journal of Lightwave Technology | Year: 2014
This paper reports an uncooled transmitter system using a digital super-mode (DS) distributed Bragg reflector (DBR) tunable laser, which is able to act as an athermal, wavelength agnostic transmitter suitable for wavelength division multiplexed (WDM) passive optical network (PON) applications. An open-loop laser current control algorithm is designed to compensate autonomously for wavelength drift, thus allowing constant operating wavelength to be achieved regardless of ambient temperature. An improved wavelength accuracy of ±3 GHz is achieved when using low bandwidth feedback from the central office using information from a centralized shared wavelength locker. The entire laser start-up, channel selection and subsequent wavelength control is autonomous and has been implemented on micro-controllers and field programmable gate arrays. We demonstrate a three channel WDM-PON system comprising an uncooled packaged DS-DBR laser in the presence of two neighboring interfering channels. Error free transmission over 40 km single mode fiber of 10 Gb/s externally modulated NRZ data, is achieved for each of 48 C-band channels on the 100 GHz ITU grid. Successful athermal operation is demonstrated by sweeping the ambient temperature of the laser from 15 to 70 °C with a maximum wavelength deviation for any channel of no more than 0.1 nm. © 1983-2012 IEEE.
Cohen G.,Oclaro Inc. |
Bala K.,Oclaro Inc.
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2011
This paper presents an overview of the requirements of the next generation dynamic mesh type reconfigurable optical add-drop multiplexer (ROADM) networks carrying optical channels at 100Gb/s and higher data rates. Liquid crystal (LC) and 1-axis Micro-Electro-Mechanical Systems (MEMS) for scalable and flexible wavelength selective switches (WSS) devices for these networks is highlighted. © 2010 COPYRIGHT SPIE - The International Society for Optical Engineering.
Couder A.,Oclaro Inc.
Photonics Spectra | Year: 2011
Alain Couder, Oclaro Inc., states that the optical communications market has experienced substantial growth, demonstrating a significant transformation from 2000 when the industry had reached the lowest level due to the massive build-out of high-speed optical communications equipment. The industry consolidation is leading to better results, optical providers are improving their financial models to reach sustainable levels that allow them to continue to reinvest in innovation and capacity expansion. Oclaro is one of the companies that has completely transformed itself into a major player in this market over a period of time. The company created through the merger of Bookham and Avanex in early 2009 has been executing against a deliberate strategy to be the predominant force in the fiber optics industry, driving industry consolidation and overcoming competition with a broad range of products and technology innovation.
Zhao J.,TU Eindhoven |
Lenstra D.,TU Eindhoven |
Santos R.,TU Eindhoven |
Wale M.J.,TU Eindhoven |
And 2 more authors.
Optics Express | Year: 2012
We experimentally and theoretically investigate the stability of a single-mode integrated filtered-feedback laser as a function of the electrically controlled feedback phase. We interpret the measurements in terms of feedback-induced dynamics, compare them with the results from a stability analysis model for conventional feedback, and find good qualitative agreement. © 2012 Optical Society of America.