A silicon-based photonic switch is proposed and simulated based on the multimode interference （MMI） principle and the free-carrier plasma dispersion effect in silicon-germanium. The proposed switch, designed for 1.5...A silicon-based photonic switch is proposed and simulated based on the multimode interference （MMI） principle and the free-carrier plasma dispersion effect in silicon-germanium. The proposed switch, designed for 1.55μm window operation,is useful for DWDM optical networks. The switch consists of two input single-mode ridge waveguide ports,a MMI section, and three output single-mode ridge waveguide ports. In the MMI section, two index-modulation regions are placed to divert input optical signals from the two input ports to each of the three output ports. Switching characteristics are demonstrated theoretically by a beam propagation method for 1.55μm operation. The simulated results show that the insertion loss of the switch is less than 1.43dB, and the crosstalk is between - 18 and - 32.8dB.展开更多
Silicon photonic switches are widely considered as a cost-effective solution for addressing the ever-growing data traffic in datacenter networks,as they offer unique advantages such as low power consumption,low latenc...Silicon photonic switches are widely considered as a cost-effective solution for addressing the ever-growing data traffic in datacenter networks,as they offer unique advantages such as low power consumption,low latency,small footprint and high bandwidth.Despite extensive research efforts,crosstalk in large-scale photonic circuits still poses a threat to signal integrity.In this paper,we present two designs of silicon Mach-Zehnder Interferometer(MZI)switches achieving ultra-low-crosstalk,driven thermally and electrically.Each switch fabric is optimized at both the device and circuit level to suppress crosstalk and reduce system complexity.Notably,for the first time to the best of our knowledge,we harness the inherent self-heating effect in a carrier-injection-based MZI switch to create a pair of phase shifters that offers arbitrary phase differences.Such a pair of phase shifters induces matched insertion loss at each arm,thus minimizing crosstalk.Experimentally,an ultra-low crosstalk ratio below−40 dB is demonstrated for both thermooptic(T-O)and electro-optic(E-O)switches.The T-O switch exhibits an on-chip loss of less than 5 dB with a switching time of 500µs,whereas the E-O switch achieves an on-chip loss as low as 8.5 dB with a switching time of under 100 ns.In addition,data transmission of a 50 Gb/s on–off keying signal is demonstrated with high fidelity on the E-O switch,showing the great potential of the proposed switch designs.展开更多
We propose and experimentally demonstrate a 2×2 thermo-optic(TO) crossbar switch implemented by dual photonic crystal nanobeam(PCN)cavities within a silicon-on-insulator(SOI)platform.By thermally tuning the refra...We propose and experimentally demonstrate a 2×2 thermo-optic(TO) crossbar switch implemented by dual photonic crystal nanobeam(PCN)cavities within a silicon-on-insulator(SOI)platform.By thermally tuning the refractive index of silicon,the resonance wavelength of the PCN cavities can be red-shifted.With the help of the ultrasmall mode volumes of the PCN cavities,only～0.16 mW power is needed to change the switching state.With a spectral passband of 0.09 nm at the 1583.75 nm operation wavelength,the insertion loss(IL)and crosstalk(CT)performances were measured as IL(bar)=-0.2 dB,CT(bar)=-15 dB,IL(cross)=-1.5 dB,and CT(cross)=-15 dB.Furthermore,the thermal tuning efficiency of the fabricated device is as high as1.23 nm/mW.展开更多
We express a photonic packet switch prototype based on optical label processing methods which dramatically increase the label processing capability. We experimentally demonstrate 40Gbit/s/port packet switching and opt...We express a photonic packet switch prototype based on optical label processing methods which dramatically increase the label processing capability. We experimentally demonstrate 40Gbit/s/port packet switching and optical buffering capabilities of the prototype.展开更多
Researchers from the CAS Key Laboratory of Quantum Information,University of Science and Technology of China have just achieved a significant progress in quantum key distribution research.Based on the self-developed a...Researchers from the CAS Key Laboratory of Quantum Information,University of Science and Technology of China have just achieved a significant progress in quantum key distribution research.Based on the self-developed active switching technology,they successfully conducted the world's longest-more than 90km-round-robin differential phase shift(RRDPS)quantum key distribution experiment.展开更多
Photonic integrated switches that are both space and wavelength selective are a highly promising technology for data-intensive applications as they benefit from multi-dimensional manipulation of optical signals.Howeve...Photonic integrated switches that are both space and wavelength selective are a highly promising technology for data-intensive applications as they benefit from multi-dimensional manipulation of optical signals.However,scaling these switches normally poses stringent challenges such as increased fabrication complexity and control difficulties,due to the growing number of switching elements.In this work,we propose a new type of dilated crosspoint topology,which efficiently handles both space and wavelength selective switching,while reducing the required switching element count by an order of magnitude compared to reported designs.To the best of our knowledge,our design requires the fewest switching elements for an equivalent routing paths number and it fully cancels the first-order in-band crosstalk.We demonstrate such an ultra-compact space-and-wavelength selective switch(SWSS)at a scale of 4×4×4λ on the silicon-on-insulator(SOI)platform.Experimental results reveal that the switch achieves an insertion loss ranging from 2.3 dB to 8.6 dB and crosstalk levels in between−35.3 dB and−59.7 dB.The add-drop microring-resonators(MRRs)are equipped with micro-heaters,exhibiting a rise and fall time of 46μs and 0.33μs,respectively.These performance characteristics highlight the switch’s ultralow element count and crosstalk with low insertion loss,making it a promising candidate for advanced data center applications.展开更多
2.5 Gbit/s ATM optical switching experimental system has been achieved for the first time in P.R.China.This poper describes the architecture of the ATM optical switching system.and gives some key technologies forreali...2.5 Gbit/s ATM optical switching experimental system has been achieved for the first time in P.R.China.This poper describes the architecture of the ATM optical switching system.and gives some key technologies forrealization,e.g. photonic switching matrix, header identification, etc. In addition, the performance, analysis andexperimental results are given.展开更多
During the past decades,nonlinear optical（NLO）materials have attracted special interest because of their potential applications in photonic devices,such as optical switching,frequency conversion and electro-optic mo...During the past decades,nonlinear optical（NLO）materials have attracted special interest because of their potential applications in photonic devices,such as optical switching,frequency conversion and electro-optic modulators.Among the finding ways to obtain excellent NLO materials with both large NLO response and short response time,展开更多
We demonstrate the generation of Q-switched pulses from an ytterbium-doped fiber laser（YDFL） using quantum dot（QD） CdSe as a passive saturable absorber（SA）. The CdSe QD is fabricated by the synthesis of CdO,Se, ...We demonstrate the generation of Q-switched pulses from an ytterbium-doped fiber laser（YDFL） using quantum dot（QD） CdSe as a passive saturable absorber（SA）. The CdSe QD is fabricated by the synthesis of CdO,Se, and manganese acetate and paraffin oil and oleic acid as the solvent and surfactant, respectively. The CdSe QD is then doped into poly-methyl-methacrylate（PMMA） via an emulsion polymerization process. A PMMAhosted CdSe QD thin flake with a homogeneous end surface is then formed and placed between two ferrules and assembled in a YDFL cavity to achieve the Q-switching operation with a repetition rate of 24.45 to 40.50 kHz while varying the pump power from 975 to 1196 mW. The pulse width changes from 6.78 to 3.65 μs with a maximum calculated pulse energy at 0.77 μJ at a pump power of 1101 mW. This work may be the first demonstration of CdSe QD-based Q-switching in an all-fiber configuration that should give proportional insight into semiconductor QD materials in photonics applications.展开更多
文摘A silicon-based photonic switch is proposed and simulated based on the multimode interference （MMI） principle and the free-carrier plasma dispersion effect in silicon-germanium. The proposed switch, designed for 1.55μm window operation,is useful for DWDM optical networks. The switch consists of two input single-mode ridge waveguide ports,a MMI section, and three output single-mode ridge waveguide ports. In the MMI section, two index-modulation regions are placed to divert input optical signals from the two input ports to each of the three output ports. Switching characteristics are demonstrated theoretically by a beam propagation method for 1.55μm operation. The simulated results show that the insertion loss of the switch is less than 1.43dB, and the crosstalk is between - 18 and - 32.8dB.
基金supported by the UK EPSRC Programme Grant QUDOS(EP/T028475/1)TRANSNET(EP/R035342/1)+3 种基金Communication Hub TITAN(EP/X04047X/1 and EP/Y037243/1)UK EPSRC CEPS CDT(EP/S022139/1)the European Union’s Horizon Europe Research and Innovation Program under Agreement 101070560(PUNCH)the European Union’s Horizon 2020 research and innovation program,project INSPIRE(101017088).
文摘Silicon photonic switches are widely considered as a cost-effective solution for addressing the ever-growing data traffic in datacenter networks,as they offer unique advantages such as low power consumption,low latency,small footprint and high bandwidth.Despite extensive research efforts,crosstalk in large-scale photonic circuits still poses a threat to signal integrity.In this paper,we present two designs of silicon Mach-Zehnder Interferometer(MZI)switches achieving ultra-low-crosstalk,driven thermally and electrically.Each switch fabric is optimized at both the device and circuit level to suppress crosstalk and reduce system complexity.Notably,for the first time to the best of our knowledge,we harness the inherent self-heating effect in a carrier-injection-based MZI switch to create a pair of phase shifters that offers arbitrary phase differences.Such a pair of phase shifters induces matched insertion loss at each arm,thus minimizing crosstalk.Experimentally,an ultra-low crosstalk ratio below−40 dB is demonstrated for both thermooptic(T-O)and electro-optic(E-O)switches.The T-O switch exhibits an on-chip loss of less than 5 dB with a switching time of 500µs,whereas the E-O switch achieves an on-chip loss as low as 8.5 dB with a switching time of under 100 ns.In addition,data transmission of a 50 Gb/s on–off keying signal is demonstrated with high fidelity on the E-O switch,showing the great potential of the proposed switch designs.
基金National Natural Science Foundation of China(NSFC)(61235007,61505104,61605112)Science and Technology Commission of Shanghai Municipality(15ZR1422800,16XD1401400)National Key R&D Program of China(2016YFB0402501)
文摘We propose and experimentally demonstrate a 2×2 thermo-optic(TO) crossbar switch implemented by dual photonic crystal nanobeam(PCN)cavities within a silicon-on-insulator(SOI)platform.By thermally tuning the refractive index of silicon,the resonance wavelength of the PCN cavities can be red-shifted.With the help of the ultrasmall mode volumes of the PCN cavities,only～0.16 mW power is needed to change the switching state.With a spectral passband of 0.09 nm at the 1583.75 nm operation wavelength,the insertion loss(IL)and crosstalk(CT)performances were measured as IL(bar)=-0.2 dB,CT(bar)=-15 dB,IL(cross)=-1.5 dB,and CT(cross)=-15 dB.Furthermore,the thermal tuning efficiency of the fabricated device is as high as1.23 nm/mW.
文摘We express a photonic packet switch prototype based on optical label processing methods which dramatically increase the label processing capability. We experimentally demonstrate 40Gbit/s/port packet switching and optical buffering capabilities of the prototype.
文摘Researchers from the CAS Key Laboratory of Quantum Information,University of Science and Technology of China have just achieved a significant progress in quantum key distribution research.Based on the self-developed active switching technology,they successfully conducted the world's longest-more than 90km-round-robin differential phase shift(RRDPS)quantum key distribution experiment.
基金Engineering and Physical Sciences Research Council (EP/T028475/1)European Union's Horizon Europe Research and Innovation Program (101070560,101017088)。
文摘Photonic integrated switches that are both space and wavelength selective are a highly promising technology for data-intensive applications as they benefit from multi-dimensional manipulation of optical signals.However,scaling these switches normally poses stringent challenges such as increased fabrication complexity and control difficulties,due to the growing number of switching elements.In this work,we propose a new type of dilated crosspoint topology,which efficiently handles both space and wavelength selective switching,while reducing the required switching element count by an order of magnitude compared to reported designs.To the best of our knowledge,our design requires the fewest switching elements for an equivalent routing paths number and it fully cancels the first-order in-band crosstalk.We demonstrate such an ultra-compact space-and-wavelength selective switch(SWSS)at a scale of 4×4×4λ on the silicon-on-insulator(SOI)platform.Experimental results reveal that the switch achieves an insertion loss ranging from 2.3 dB to 8.6 dB and crosstalk levels in between−35.3 dB and−59.7 dB.The add-drop microring-resonators(MRRs)are equipped with micro-heaters,exhibiting a rise and fall time of 46μs and 0.33μs,respectively.These performance characteristics highlight the switch’s ultralow element count and crosstalk with low insertion loss,making it a promising candidate for advanced data center applications.
文摘2.5 Gbit/s ATM optical switching experimental system has been achieved for the first time in P.R.China.This poper describes the architecture of the ATM optical switching system.and gives some key technologies forrealization,e.g. photonic switching matrix, header identification, etc. In addition, the performance, analysis andexperimental results are given.
基金supported by the National Natural Science Foundation of China(Grant No.11474046)Program for New Century Excellent Talents in University(Grant No.NCET-13-0702)+3 种基金Fundamental Research Funds for the Central Universities(Grant Nos.DC201502080202,and DC201502080203)Program for Liaoning Excellent Talents in University(LNET)(Grant No.LR2015016)Science and Technique Foundation of Dalian(Grant Nos.2014J11JH134,and 2015J12JH201)Education Department of Liaoning Province of China.
文摘During the past decades,nonlinear optical（NLO）materials have attracted special interest because of their potential applications in photonic devices,such as optical switching,frequency conversion and electro-optic modulators.Among the finding ways to obtain excellent NLO materials with both large NLO response and short response time,
文摘We demonstrate the generation of Q-switched pulses from an ytterbium-doped fiber laser（YDFL） using quantum dot（QD） CdSe as a passive saturable absorber（SA）. The CdSe QD is fabricated by the synthesis of CdO,Se, and manganese acetate and paraffin oil and oleic acid as the solvent and surfactant, respectively. The CdSe QD is then doped into poly-methyl-methacrylate（PMMA） via an emulsion polymerization process. A PMMAhosted CdSe QD thin flake with a homogeneous end surface is then formed and placed between two ferrules and assembled in a YDFL cavity to achieve the Q-switching operation with a repetition rate of 24.45 to 40.50 kHz while varying the pump power from 975 to 1196 mW. The pulse width changes from 6.78 to 3.65 μs with a maximum calculated pulse energy at 0.77 μJ at a pump power of 1101 mW. This work may be the first demonstration of CdSe QD-based Q-switching in an all-fiber configuration that should give proportional insight into semiconductor QD materials in photonics applications.
