634 research outputs found
A 160-Gb/s OTDM demultiplexer based on parametric wavelength exchange
Parametric wavelength exchange (PWE) has been demonstrated as a versatile device in providing different functionalities. In this paper, we will concentrate, numerically and experimentally, on one of these functionalities, namely, all-optical time demultiplexing of 160-Gb/s return-to-zero (RZ) signals based on a pulsed-pump PWE in a 400 m highly nonlinear dispersion-shifted fiber. Experimental results show power penalties < 2.7 dB at bit-error rate of 10-9 for all demultiplexed 10-Gb/s RZ signals. We also derive theoretical expressions for the conversion/residual efficiencies and investigate the impact of pump pulse width and phase mismatch on these efficiencies. Furthermore, the impacts of pulsed-pump wavelength and power level on the characteristics of the switching window are investigated numerically. As a result, the demultiplexer can be easily upgraded to an add-drop multiplexer because of the complete exchange nature of PWE, which is justified by the surviving channels' waveform performance. © 2009 IEEE.published_or_final_versio
A 160-Gb/s OTDM demultiplexer based on parametric wavelength exchange
Parametric wavelength exchange (PWE) has been demonstrated as a versatile device in providing different functionalities. In this paper, we will concentrate, numerically and experimentally, on one of these functionalities, namely, all-optical time demultiplexing of 160-Gb/s return-to-zero (RZ) signals based on a pulsed-pump PWE in a 400 m highly nonlinear dispersion-shifted fiber. Experimental results show power penalties < 2.7 dB at bit-error rate of 10-9 for all demultiplexed 10-Gb/s RZ signals. We also derive theoretical expressions for the conversion/residual efficiencies and investigate the impact of pump pulse width and phase mismatch on these efficiencies. Furthermore, the impacts of pulsed-pump wavelength and power level on the characteristics of the switching window are investigated numerically. As a result, the demultiplexer can be easily upgraded to an add-drop multiplexer because of the complete exchange nature of PWE, which is justified by the surviving channels' waveform performance. © 2009 IEEE.published_or_final_versio
Multi-dimensional entanglement generation with multi-core optical fibers
Trends in photonic quantum information follow closely the technical progress
in classical optics and telecommunications. In this regard, advances in
multiplexing optical communications channels have also been pursued for the
generation of multi-dimensional quantum states (qudits), since their use is
advantageous for several quantum information tasks. One current path leading in
this direction is through the use of space-division multiplexing multi-core
optical fibers, which provides a new platform for efficiently controlling
path-encoded qudit states. Here we report on a parametric down-conversion
source of entangled qudits that is fully based on (and therefore compatible
with) state-of-the-art multi-core fiber technology. The source design uses
modern multi-core fiber beam splitters to prepare the pump laser beam as well
as measure the generated entangled state, achieving high spectral brightness
while providing a stable architecture. In addition, it can be readily used with
any core geometry, which is crucial since widespread standards for multi-core
fibers in telecommunications have yet to be established. Our source represents
an important step towards the compatibility of quantum communications with the
next-generation optical networks.Comment: 9 pages, 7 figure
Coexistence of continuous variable QKD with intense DWDM classical channels
We demonstrate experimentally the feasibility of continuous variable quantum
key distribution (CV-QKD) in dense-wavelength-division multiplexing networks
(DWDM), where QKD will typically have to coexist with several co- propagating
(forward or backward) C-band classical channels whose launch power is around
0dBm. We have conducted experimental tests of the coexistence of CV-QKD
multiplexed with an intense classical channel, for different input powers and
different DWDM wavelengths. Over a 25km fiber, a CV-QKD operated over the
1530.12nm channel can tolerate the noise arising from up to 11.5dBm classical
channel at 1550.12nm in forward direction (9.7dBm in backward). A positive key
rate (0.49kb/s) can be obtained at 75km with classical channel power of
respectively -3dBm and -9dBm in forward and backward. Based on these
measurements, we have also simulated the excess noise and optimized channel
allocation for the integration of CV-QKD in some access networks. We have, for
example, shown that CV-QKD could coexist with 5 pairs of channels (with nominal
input powers: 2dBm forward and 1dBm backward) over a 25km WDM-PON network. The
obtained results demonstrate the outstanding capacity of CV-QKD to coexist with
classical signals of realistic intensity in optical networks.Comment: 19 pages, 9 figures. Revised version, to appear in New Journal of
Physic
Qubit entanglement between ring-resonator photon-pair sources on a silicon chip
Entanglementâone of the most delicate phenomena in natureâis an essential resource for quantum information applications. Scalable photonic quantum devices must generate and control qubit entanglement on-chip, where quantum information is naturally encoded in photon path. Here we report a silicon photonic chip that uses resonant-enhanced photon-pair sources, spectral demultiplexers and reconfigurable optics to generate a path-entangled two-qubit state and analyse its entanglement. We show that ring-resonator-based spontaneous four-wave mixing photon-pair sources can be made highly indistinguishable and that their spectral correlations are small. We use on-chip frequency demultiplexers and reconfigurable optics to perform both quantum state tomography and the strict Bell-CHSH test, both of which confirm a high level of on-chip entanglement. This work demonstrates the integration of high-performance components that will be essential for building quantum devices and systems to harness photonic entanglement on the large scale
Study On All-Optical Signal Processing by Semiconductor Optical Amplifiers for Ultra-High-Speed Optical Fiber Communications
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Visible WDM system for real-time multi-Gb/s bidirectional transmission over 50-m SI-POF
We report a 2 Gb/s bidirectional real-time data transmission with bit error rate (BER) < 1 x 10(-10) in a 50 m step-index polymer optical fiber link. The system is able to transmit 5 Gb/s using five channels. The system performance is tested using the most restrictive channels with the shortest and longest wavelengths in a real-time Ethernet link. The implementation takes an advantage of the PAM-16 modulation spectral efficiency and low loss multiplexers and demultiplexers, which provide an enhanced link power budget. The optical power per transmitted bit considering the BER implication for TCP/IP networks throughput is below 5.8 pJ/b. This is due to the low insertion losses <4 dB, in each five-channel multiplexer and demultiplexer.This work was supported in part by the Spanish Ministry of Economy under Grants TEC2012-37983-C03-02 and TEC2015-63826-C3-2-R, and in part by Madrid Region under Grant S2013/MIT-2790
Inverse design of nano-photonic wavelength demultiplexer with a deep neural network approach
In this paper, we propose a pre-trained-combined neural network (PTCN) as a
comprehensive solution to the inverse design of an integrated photonic circuit.
By utilizing both the initially pre-trained inverse and forward model with a
joint training process, our PTCN model shows remarkable tolerance to the
quantity and quality of the training data. As a proof of concept demonstration,
the inverse design of a wavelength demultiplexer is used to verify the
effectiveness of the PTCN model. The correlation coefficient of the prediction
by the presented PTCN model remains greater than 0.974 even when the size of
training data is decreased to 17%. The experimental results show a good
agreement with predictions, and demonstrate a wavelength demultiplexer with an
ultra-compact footprint, a high transmission efficiency with a transmission
loss of -2dB, a low reflection of -10dB, and low crosstalk around -7dB
simultaneously
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