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
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CICQ(Combined Input Crosspoint Queued)是一种在crossbar交叉点加入少量缓存的交换结构,具有无需内部加速比及分布并行调度的特性。为了自适应网络环境中各种业务流量,提高在非均匀流量下的性能,该文提出了一种基于最长队列预测的高效CICQ交换结构调度算法——RR-LQD(Round Robin with Longest Queue Detecting)。RR-LQD算法复杂度为O(1),具有良好的可扩展性;通过预测局部"最长"队列并尽力为其服务,保持调度中队列长度的均衡,能够适应各种非均匀流量的网络环境。仿真结果表明:在各种均匀和非均匀流量下,RR-LQD算法均能达到100%的吞吐量,并且具有优良的时延性能。该文使用FPGA芯片实现了RR-LQD算法仲裁器,能够满足高速、大容量交换结构的设计需要。