We propose a novel high-performance digital optical sensor based on the Mach-Zehnder interferential effect and the dual-microring resonators with the waveguide-coupled feedback. The simulation results show that the se...We propose a novel high-performance digital optical sensor based on the Mach-Zehnder interferential effect and the dual-microring resonators with the waveguide-coupled feedback. The simulation results show that the sensitivity of the sensor can be orders of magnitude higher than that of aconventional sensor, and high quality factor is not critical in it. Moreover, by optimizing the length of the feedback waveguide to be equal to the perimeter of the ring, the measurement range of the proposed sensor is twice as much as that of the conventional sensor in the weak coupling case.展开更多
This paper investigated the design and the characterization of a photonic delay line based on passive cascaded silicon-on-insulator (SOI) microrings. We considered the compromise of group delay, bandwidth and insert...This paper investigated the design and the characterization of a photonic delay line based on passive cascaded silicon-on-insulator (SOI) microrings. We considered the compromise of group delay, bandwidth and insertion loss. A 3-stage double channel side-coupled integrated spaced sequence of resonator (SCISSOR) device was optimized by shifting the resonance of each microring and fabricated with electron beam lithography and dry etching. The group delay was measured to be 17 ps for non-return-to-zero signals at different bit rates and the bandwidth of 78 GHz was achieved. The experiment result agreed well with our simulation.展开更多
We designed a reconfigurable dual-interferometer coupled silicon nitride microring resonator.By tuning the integrated heater on interferometer's arms,the"critical coupling"bandwidth of resonant mode is c...We designed a reconfigurable dual-interferometer coupled silicon nitride microring resonator.By tuning the integrated heater on interferometer's arms,the"critical coupling"bandwidth of resonant mode is continuously adjustable whose quality factor varies from 7.9×10^(4) to 1.9×10^(5) with the extinction ratio keeping higher than 25 dB.Also a variety of coupling spanning from"under-coupling"to"over-coupling"were achieved,showing the ability to tune the quality factor from 6.0×10^(3) to 2.3×10^(5).Our design can provide an adjustable filtering method on silicon nitride photonic chip and contribute to optimize the nonlinear process for quantum photonics and all-optical signal processing.展开更多
A high-performance microring resonator in a silicon-on-insulator rib waveguide is realized by using the electron beam lithography followed by inductively coupled plasma etching. The design and the experimental realiza...A high-performance microring resonator in a silicon-on-insulator rib waveguide is realized by using the electron beam lithography followed by inductively coupled plasma etching. The design and the experimental realization of this device are presented in detail. In addition to improving relevant processes to minimize propagation loss, the coupling efficiency between the ring and the bus is carefully chosen to approach a critical coupling for high performance operating. We have measured a quality factor of 21,200 and an extinction ratio of 12.SdB at a resonant wavelength of 1549.32nm. Meanwhile, a low propagation loss of 0.89dB/mm in a curved waveguide with a bending radius of 40μm is demonstrated as well.展开更多
We propose a novel resonator containing an elliptical microring based on a silicon-on-insulator platform. Simu- lations using the three-dimensional finite-difference time-domain method show that the novel elliptical m...We propose a novel resonator containing an elliptical microring based on a silicon-on-insulator platform. Simu- lations using the three-dimensional finite-difference time-domain method show that the novel elliptical microring can efficiently enhance the mode coupling between straight bus waveguides and resonator waveguides or between adjacent resonators while preserving relatively high intrinsic quality factors with large free spectral range. The proposed resonator would be an alternative choice for future high-density integrated photonic circuits.展开更多
High-dimensional entanglement provides valuable resources for quantum technologies,including quantum communication,quantum optical coherence tomography,and quantum computing.Obtaining a high brightness and dimensional...High-dimensional entanglement provides valuable resources for quantum technologies,including quantum communication,quantum optical coherence tomography,and quantum computing.Obtaining a high brightness and dimensional entanglement source has significant value.Here we utilize a tunable asymmetric Mach–Zehnder interferometer coupled silicon microring resonator with 100 GHz free spectral range to achieve this goal.With the strategy of the tunable coupler,the dynamical and extensive tuning range of quality factors of the microring can be obtained,and then the biphoton pair generation rate can be optimized.By selecting and characterizing 28 pairs from a more than 30-pair modes biphoton frequency comb,we obtain a Schmidt number of at least 23.4 and on-chip pair generation rate of 19.9 MHz/m W;under a low on-chip pump power,which corresponds to 547 dimensions Hilbert space in frequency freedom.These results will prompt the wide applications of quantum frequency comb and boost the further large density and scalable on-chip quantum information processing.展开更多
We report on an eight-channel reconfigurable optical add-drop multiplexer based on cascaded microring resonators with a high tuning power consumption and a compact footprint. Microheaters are fabricated on top of the ...We report on an eight-channel reconfigurable optical add-drop multiplexer based on cascaded microring resonators with a high tuning power consumption and a compact footprint. Microheaters are fabricated on top of the microring resonators and can be modulated using the thermo-optic effect to achieve the reconfigurable functionality of the device. We demonstrate the reconfigurable add-drop multiplexing functionality for channel spacings of 1 O0 GHz and 50 GHz, with the centre wavelengths of the channels aligned to International Telecommunication Union grid specifications. The crosstalk for channel spacings of 100 GHz and 50 GHz are less than -22.5 dB and -15.5 dB, respectively. The average tuning efficiency is about 4.5 mW/nm, and the response speed is about 13.0 kHz.展开更多
In terms of the coupled mode theory, microring resonance and electro-optic modulation princeple, a reasonable project is proposed for designing an electro-optic switch with the series-coupled multiple microring resona...In terms of the coupled mode theory, microring resonance and electro-optic modulation princeple, a reasonable project is proposed for designing an electro-optic switch with the series-coupled multiple microring resonators. The simulation and optimization are performed at the resonant wavelength of 1550 nm. The results are as follows: the core size of the microring is 1.6 μm×1.6 μm, the confined layer between the core and the electrode is 1.6 μm, the thickness of the electrode is 0.15 μm, the radius of the microring is 15.2 μm, the coupling gap between the microring and the channel is 0.14 μm, and the one between the microring and the microring is 0.6 μm, microring number M is 4, the switching voltage is 4 V, the insertion loss is 5.4 dB, and the crosstalk is –20 dB. The output spectrum is much flatter and much steeper than that of the single microring.展开更多
A wide range (9.4nm) tuning of vertically coupled microring resonator filter was demonstrated utilizing a large TO coefficient of polymer. The power consumption was about 60m W and no degradation of filter response wa...A wide range (9.4nm) tuning of vertically coupled microring resonator filter was demonstrated utilizing a large TO coefficient of polymer. The power consumption was about 60m W and no degradation of filter response was observed.展开更多
The effects of manufacturing errors on transmission characteristics are analyzed for a polymer vertical coupling microring resonator.Calculated results show that the errors cause a shift and shape change of the transm...The effects of manufacturing errors on transmission characteristics are analyzed for a polymer vertical coupling microring resonator.Calculated results show that the errors cause a shift and shape change of the transmission spectrum compared to the designed case without errors.Furthermore,accumulation and compensation for the errors is researched.In order to realize the normal filtering for the fabricated microring resonator device,some allowed errors are discussed.展开更多
A system of an add-drop microring resonator integrated with a sampled grating distributed feedback (SG-DFB) is investigated via modeling and simulation with the time-domain traveling wave (TDTW) method. The propos...A system of an add-drop microring resonator integrated with a sampled grating distributed feedback (SG-DFB) is investigated via modeling and simulation with the time-domain traveling wave (TDTW) method. The proposed microring resonator comprises a SiO2 waveguide integrated with an InGaAsP/InP SG-DFB, and the SiO2 waveguide consists of a silicon core having a refractive index of 3.48 and Kerr co- efficient of 4.5 × 10^-18 m2/W. The SG-DFB consists of a series of grating bursts that are constructed using a periodic apodization function with a burst spacing in the grating of 45 μm, a burst length of 5 μm, and I0 bursts across the total length of the SG-DBR. Transmission results of the through and drop port of the microring resonator show the significant capacity enhancement of the generated center wavelengths. The Q-factor of the microring resonator system, defined as the center wavelength (λ0) divided by 3 dB FWHM, without and with integration with the SG-DFB is calculated as 1.93 × 10^5 and 2.87 × 10^5, respectively. Analysis of the dispersion of the system reveals that increasing the wavelength results in a decrease of the dispersion. The higher capacity and efficiency are the advantages of integrating the microring resonator and the InGaAsP/InP SG-DFB.展开更多
We propose and experimentally demonstrate compact on-chip 1×2 wavelength selective switches(WSSs) based on silicon microring resonators(MRRs) with nested pairs of subrings(NPSs). Owing to the resonance splitting ...We propose and experimentally demonstrate compact on-chip 1×2 wavelength selective switches(WSSs) based on silicon microring resonators(MRRs) with nested pairs of subrings(NPSs). Owing to the resonance splitting induced by the inner NPSs, the proposed devices are capable of performing selective channel routing at certain resonance wavelengths of the outer MRRs. System demonstration of dynamic channel routing using fabricated devices with one and two NPSs is carried out for 10 Gb∕s non-return-to-zero signal. The experimental results verify the effectiveness of the fabricated devices as compact on-chip WSSs.展开更多
An approach to the simultaneous optical ring resonators is proposed measurement of refractive-index (RI) and theoretically demonstrated. With and temperature changes using a liquid-core silica ring resonator as an e...An approach to the simultaneous optical ring resonators is proposed measurement of refractive-index (RI) and theoretically demonstrated. With and temperature changes using a liquid-core silica ring resonator as an example, two different-order whispering gallery modes (WGMs) might differ in not only RI but also temperature sensitivities. Thus, a second-order sensing matrix should be defined based on these WGMs to determine RI and temperature changes simultaneously. The analysis shows that the RI and temperature detection limits can be achieved on the order of 10.7 RI unit and 10-3 K at a wavelength of approximately 780 nm.展开更多
To achieve photon-pair generation scaling, we optimize the quality factor of microring resonators for efficient continuous-wave-pumped spontaneous four-wave mixing. Numerical studies indicate that a high intrinsic qua...To achieve photon-pair generation scaling, we optimize the quality factor of microring resonators for efficient continuous-wave-pumped spontaneous four-wave mixing. Numerical studies indicate that a high intrinsic quality factor makes high pair rate and pair brightness possible, in which the maximums take place under overcoupling and critical-coupling conditions, respectively. We fabricate six all-pass-type microring resonator samples on a silicon-on-insulator chip involving gap width as the only degree of freedom. The signal count rate, pair brightness,and coincidence rate of all the samples are characterized, which are then compared with the modified simulations by taking the detector saturation and nonlinear loss into account. Being experimentally validated for the first time to the best of our knowledge, this work explicitly demonstrates that reducing the round-trip loss in a ring cavity and designing the corresponding optimized gap width are more effective to generate high-rate or high-brightness photon pairs than the conventional strategy of simply increasing the quality factor.展开更多
In this review, the recent progress in the development of vertically coupled micro-ring resonator filters is summarized and the potential applications of the filters leading to the development of VLSI photonics are de...In this review, the recent progress in the development of vertically coupled micro-ring resonator filters is summarized and the potential applications of the filters leading to the development of VLSI photonics are described.展开更多
To research the effect of a deposited SiO2 insulating layer on the resonance frequency modulation of an SOI nanowaveguide ring cavity during integration fabrication, a rib waveguide ring resonator was systemati- cally...To research the effect of a deposited SiO2 insulating layer on the resonance frequency modulation of an SOI nanowaveguide ring cavity during integration fabrication, a rib waveguide ring resonator was systemati- cally designed and fabricated. SiO2 insulating layers with different thicknesses were deposited for analysis of the frequency shift characteristics. By testing the resonance transmission spectrum power of this structure, it is found that there are blue shifts after SiO2 deposition, and the frequency shift value of a structure with a 500 nm SiO2 insulating layer deposited is 0.8 nm, that is 0.24 THz at the resonance point where wavelength is around 1550 nm. Taking advantage of this conclusion, efficient optical modulation is available by choosing different frequency band resonance wavelengths to narrow the frequency modulation range.展开更多
By using the coupled mode theory and the transfer matrix technique,the optical transfer function is presented for analyzing the size of the waveguide,radius of the microring,free spectral range and amplitude coupling ...By using the coupled mode theory and the transfer matrix technique,the optical transfer function is presented for analyzing the size of the waveguide,radius of the microring,free spectral range and amplitude coupling ratio of the vertical coupling microring resonator.Under the central wavelength of 1550 nm,optimization and simulation are performed when the central deviation between the ring and the channel is 0,0.5,1μm,respectively, the 3-dB bandwidth of the spectral response is about 0.21,0.09,0.03 nm,and the intensity of the nonresonant light is below-30,-40,-50 dB,respectively.展开更多
The microring resonator has received increas- ing attention in the optical sensing application because of its micro-size, optical property, and high sensitivity. An additional waveguide is commonly used to change the ...The microring resonator has received increas- ing attention in the optical sensing application because of its micro-size, optical property, and high sensitivity. An additional waveguide is commonly used to change the output spectra in the early research on microring resonators. In this study, we proposed a nested microring resonator that doubles the free spectral range (FSR) compared with the conventional single microring. This structure improved the sensing property as the FSR in the filter output spectra could be considered as a measurement range in the microring sensor. Moreover, the parameters including the coupling coefficient of the three coupling sections, length of the U-bend waveguide, and effective index of a waveguide were tested and carefully selected to optimize the sensing properties. The relationship between these parameters and the output spectra was demonstrated. With linear sensitivity, the structure has a good potential in sensing application.展开更多
We demonstrate a directed optical decoder device consisting of two cascaded microring resonators, which are both modulated through the plasma dispersion effect. The inherent resonance wavelength mismatch between two m...We demonstrate a directed optical decoder device consisting of two cascaded microring resonators, which are both modulated through the plasma dispersion effect. The inherent resonance wavelength mismatch between two microring resonators caused by fabrication errors is compensated for by using microheaters that are fabricated on top of the microring resonators. Two electrical signals generated by pulse pattern generators are used to modulate the PIN diodes that are embedded in the device, and the results are presented by optical signals detected at the four output ports of the device. The working wavelength and driving voltages of two MRRs are measured and analyzed by the static response spectra of the device. Dynamic experimental results show that the decoding operation is achieved at a speed of 100 Mbps.展开更多
A compact and fabrication friendly polarization demultiplexer(P-DEMUX) is proposed and characterized to enable wavelength-division-multiplexing and polarization-division-multiplexing simultaneously. The proposed struc...A compact and fabrication friendly polarization demultiplexer(P-DEMUX) is proposed and characterized to enable wavelength-division-multiplexing and polarization-division-multiplexing simultaneously. The proposed structure is composed of a polarization-selective microring resonator in ultrathin waveguide and two bus channels in the silicon nitridesilica-silicon horizontal slot waveguides. In the slot waveguide, the transverse electric(TE) mode propagates through the silicon layer, while the transverse magnetic(TM) mode is confined in the slot region. In the designed ultra-thin waveguide, the TM mode is cut-off. The effective indexes of the TE modes for ultrathin and slot waveguides have comparable values. Thanks for these distinguishing features, the input TE mode can be efficiently filtered through the ultra-thin microring at the resonant wavelength, while the TM mode can directly output from the through port. Simulation results show that the extinction ratio of the proposed P-DEMUX for TE and TM modes are 33.21 dB and 24.97 dB, and the insertion losses are 0.346 dB and 0.324 dB, respectively, at the wavelength of 1551.64 nm. Furthermore, the device shows a broad bandwidth(> 100 nm) for an extinction ratio(ER) of > 20 dB. In addition, the proposed P-DEMUX also has a good fabrication tolerance for the waveguide width variation of-20 nm≤ △w_(g)≤ 20 nm and the microring width variation of -20 nm≤ △w_(r) ≤20 nm for a low insertion loss of < 0.75 dB and low ER of <-18 dB.展开更多
基金Project supported by the National Basic Research Program of China(Grant No.2010CB327601)
文摘We propose a novel high-performance digital optical sensor based on the Mach-Zehnder interferential effect and the dual-microring resonators with the waveguide-coupled feedback. The simulation results show that the sensitivity of the sensor can be orders of magnitude higher than that of aconventional sensor, and high quality factor is not critical in it. Moreover, by optimizing the length of the feedback waveguide to be equal to the perimeter of the ring, the measurement range of the proposed sensor is twice as much as that of the conventional sensor in the weak coupling case.
基金Project supported by the National Basic Research Program of China (Grant Nos.2006CB302803 and 2011CB301701)the National Natural Science Foundation of China (Grant No.60877036)+1 种基金State Key Laboratory of Advanced Optical Communication Systems and Networks of China (Grant No.2008SH02)the Knowledge Innovation Program of Institute of Semiconductors,Chinese Academy of Sciences (Grant No.ISCAS2008T10)
文摘This paper investigated the design and the characterization of a photonic delay line based on passive cascaded silicon-on-insulator (SOI) microrings. We considered the compromise of group delay, bandwidth and insertion loss. A 3-stage double channel side-coupled integrated spaced sequence of resonator (SCISSOR) device was optimized by shifting the resonance of each microring and fabricated with electron beam lithography and dry etching. The group delay was measured to be 17 ps for non-return-to-zero signals at different bit rates and the bandwidth of 78 GHz was achieved. The experiment result agreed well with our simulation.
基金the National Key Research and Development Program of China(Grant Nos.2019YFA0308700and 2017YFA0303700)the National Natural Science Foundation of China(Grant Nos.11627810 and 11690031)the Open Funds from the State Key Laboratory of High Performance Computing of China(HPCL,National University of Defense Technology).
文摘We designed a reconfigurable dual-interferometer coupled silicon nitride microring resonator.By tuning the integrated heater on interferometer's arms,the"critical coupling"bandwidth of resonant mode is continuously adjustable whose quality factor varies from 7.9×10^(4) to 1.9×10^(5) with the extinction ratio keeping higher than 25 dB.Also a variety of coupling spanning from"under-coupling"to"over-coupling"were achieved,showing the ability to tune the quality factor from 6.0×10^(3) to 2.3×10^(5).Our design can provide an adjustable filtering method on silicon nitride photonic chip and contribute to optimize the nonlinear process for quantum photonics and all-optical signal processing.
基金supported by the State Key Development Program for Basic Research of China (Grant Nos 2006CB302803 and2007CB613405)the National High Technology Research and Development Program of China (Grant No 2006AA03Z424)the National Natural Science Foundation of China (Grant No 60577044)
文摘A high-performance microring resonator in a silicon-on-insulator rib waveguide is realized by using the electron beam lithography followed by inductively coupled plasma etching. The design and the experimental realization of this device are presented in detail. In addition to improving relevant processes to minimize propagation loss, the coupling efficiency between the ring and the bus is carefully chosen to approach a critical coupling for high performance operating. We have measured a quality factor of 21,200 and an extinction ratio of 12.SdB at a resonant wavelength of 1549.32nm. Meanwhile, a low propagation loss of 0.89dB/mm in a curved waveguide with a bending radius of 40μm is demonstrated as well.
基金Project supported by the National Basic Research Program of China (Grant Nos. 2011CB301701, 2012CB933502, and2012CB933504)the National Natural Science Foundation of China (Grant Nos. 60877036 and 61107048)the Knowledge Innovation Program of the Chinese Academy of Sciences (Grant No. KGCX2-EW-102)
文摘We propose a novel resonator containing an elliptical microring based on a silicon-on-insulator platform. Simu- lations using the three-dimensional finite-difference time-domain method show that the novel elliptical microring can efficiently enhance the mode coupling between straight bus waveguides and resonator waveguides or between adjacent resonators while preserving relatively high intrinsic quality factors with large free spectral range. The proposed resonator would be an alternative choice for future high-density integrated photonic circuits.
基金supported by the National Basic Research Program of China(Grant Nos.2019YFA0308700 and 2017YFA0303700)the National Natural Science Foundation of China(Grant Nos.61632021 and 11690031)the Open Funds from the State Key Laboratory of High Performance Computing of China(HPCL,National University of Defense Technology)。
文摘High-dimensional entanglement provides valuable resources for quantum technologies,including quantum communication,quantum optical coherence tomography,and quantum computing.Obtaining a high brightness and dimensional entanglement source has significant value.Here we utilize a tunable asymmetric Mach–Zehnder interferometer coupled silicon microring resonator with 100 GHz free spectral range to achieve this goal.With the strategy of the tunable coupler,the dynamical and extensive tuning range of quality factors of the microring can be obtained,and then the biphoton pair generation rate can be optimized.By selecting and characterizing 28 pairs from a more than 30-pair modes biphoton frequency comb,we obtain a Schmidt number of at least 23.4 and on-chip pair generation rate of 19.9 MHz/m W;under a low on-chip pump power,which corresponds to 547 dimensions Hilbert space in frequency freedom.These results will prompt the wide applications of quantum frequency comb and boost the further large density and scalable on-chip quantum information processing.
文摘We report on an eight-channel reconfigurable optical add-drop multiplexer based on cascaded microring resonators with a high tuning power consumption and a compact footprint. Microheaters are fabricated on top of the microring resonators and can be modulated using the thermo-optic effect to achieve the reconfigurable functionality of the device. We demonstrate the reconfigurable add-drop multiplexing functionality for channel spacings of 1 O0 GHz and 50 GHz, with the centre wavelengths of the channels aligned to International Telecommunication Union grid specifications. The crosstalk for channel spacings of 100 GHz and 50 GHz are less than -22.5 dB and -15.5 dB, respectively. The average tuning efficiency is about 4.5 mW/nm, and the response speed is about 13.0 kHz.
基金supported by the National Natural ScienceFoundation of China (60706011)the National "973" Project ofChina(2006CB302803)+1 种基金the Fund of Chinese Ministry of Educa-tion (20070183087)the Fund of Science and Technology ofJilin Province of China(20080125).
文摘In terms of the coupled mode theory, microring resonance and electro-optic modulation princeple, a reasonable project is proposed for designing an electro-optic switch with the series-coupled multiple microring resonators. The simulation and optimization are performed at the resonant wavelength of 1550 nm. The results are as follows: the core size of the microring is 1.6 μm×1.6 μm, the confined layer between the core and the electrode is 1.6 μm, the thickness of the electrode is 0.15 μm, the radius of the microring is 15.2 μm, the coupling gap between the microring and the channel is 0.14 μm, and the one between the microring and the microring is 0.6 μm, microring number M is 4, the switching voltage is 4 V, the insertion loss is 5.4 dB, and the crosstalk is –20 dB. The output spectrum is much flatter and much steeper than that of the single microring.
文摘A wide range (9.4nm) tuning of vertically coupled microring resonator filter was demonstrated utilizing a large TO coefficient of polymer. The power consumption was about 60m W and no degradation of filter response was observed.
基金supported by the Science and Technology Development of Jilin Province.China(Nos.20110320.201201078)
文摘The effects of manufacturing errors on transmission characteristics are analyzed for a polymer vertical coupling microring resonator.Calculated results show that the errors cause a shift and shape change of the transmission spectrum compared to the designed case without errors.Furthermore,accumulation and compensation for the errors is researched.In order to realize the normal filtering for the fabricated microring resonator device,some allowed errors are discussed.
基金Grant number LRGS(2015)NGOD/UM/KPT,RU007/2015 and RUG OF UTM,09H77 and 10J97 from the university of Malaya (UM) and Universiti Teknologi Malaysia (UTM)
文摘A system of an add-drop microring resonator integrated with a sampled grating distributed feedback (SG-DFB) is investigated via modeling and simulation with the time-domain traveling wave (TDTW) method. The proposed microring resonator comprises a SiO2 waveguide integrated with an InGaAsP/InP SG-DFB, and the SiO2 waveguide consists of a silicon core having a refractive index of 3.48 and Kerr co- efficient of 4.5 × 10^-18 m2/W. The SG-DFB consists of a series of grating bursts that are constructed using a periodic apodization function with a burst spacing in the grating of 45 μm, a burst length of 5 μm, and I0 bursts across the total length of the SG-DBR. Transmission results of the through and drop port of the microring resonator show the significant capacity enhancement of the generated center wavelengths. The Q-factor of the microring resonator system, defined as the center wavelength (λ0) divided by 3 dB FWHM, without and with integration with the SG-DFB is calculated as 1.93 × 10^5 and 2.87 × 10^5, respectively. Analysis of the dispersion of the system reveals that increasing the wavelength results in a decrease of the dispersion. The higher capacity and efficiency are the advantages of integrating the microring resonator and the InGaAsP/InP SG-DFB.
基金supported in part by the National Natural Science Foundation of China under Grant 61125504/61235007in part by the 863 High-Tech Program under Grant 2013AA013402
文摘We propose and experimentally demonstrate compact on-chip 1×2 wavelength selective switches(WSSs) based on silicon microring resonators(MRRs) with nested pairs of subrings(NPSs). Owing to the resonance splitting induced by the inner NPSs, the proposed devices are capable of performing selective channel routing at certain resonance wavelengths of the outer MRRs. System demonstration of dynamic channel routing using fabricated devices with one and two NPSs is carried out for 10 Gb∕s non-return-to-zero signal. The experimental results verify the effectiveness of the fabricated devices as compact on-chip WSSs.
基金supported by the National "973" Program of China (No. 2011CB013000)the National Natural Science Foundation of China (Nos. 90923039and 51025521)
文摘An approach to the simultaneous optical ring resonators is proposed measurement of refractive-index (RI) and theoretically demonstrated. With and temperature changes using a liquid-core silica ring resonator as an example, two different-order whispering gallery modes (WGMs) might differ in not only RI but also temperature sensitivities. Thus, a second-order sensing matrix should be defined based on these WGMs to determine RI and temperature changes simultaneously. The analysis shows that the RI and temperature detection limits can be achieved on the order of 10.7 RI unit and 10-3 K at a wavelength of approximately 780 nm.
基金National Natural Science Foundation of China(NSFC)(60907003)Natural Science Foundation of Hunan Province,China(13JJ3001)+2 种基金Program for New Century Excellent Talents in University(NCET),China(NCET-12-0142)Danmarks Grundforskningsfond(DNRF)(DNRF123)China Scholarship Council(CSC)
文摘To achieve photon-pair generation scaling, we optimize the quality factor of microring resonators for efficient continuous-wave-pumped spontaneous four-wave mixing. Numerical studies indicate that a high intrinsic quality factor makes high pair rate and pair brightness possible, in which the maximums take place under overcoupling and critical-coupling conditions, respectively. We fabricate six all-pass-type microring resonator samples on a silicon-on-insulator chip involving gap width as the only degree of freedom. The signal count rate, pair brightness,and coincidence rate of all the samples are characterized, which are then compared with the modified simulations by taking the detector saturation and nonlinear loss into account. Being experimentally validated for the first time to the best of our knowledge, this work explicitly demonstrates that reducing the round-trip loss in a ring cavity and designing the corresponding optimized gap width are more effective to generate high-rate or high-brightness photon pairs than the conventional strategy of simply increasing the quality factor.
文摘In this review, the recent progress in the development of vertically coupled micro-ring resonator filters is summarized and the potential applications of the filters leading to the development of VLSI photonics are described.
基金Project supported by the National Natural Science Foundation of China(No.61076111)the National Scientific Instruments Basic Research Program of China(No.61127008)
文摘To research the effect of a deposited SiO2 insulating layer on the resonance frequency modulation of an SOI nanowaveguide ring cavity during integration fabrication, a rib waveguide ring resonator was systemati- cally designed and fabricated. SiO2 insulating layers with different thicknesses were deposited for analysis of the frequency shift characteristics. By testing the resonance transmission spectrum power of this structure, it is found that there are blue shifts after SiO2 deposition, and the frequency shift value of a structure with a 500 nm SiO2 insulating layer deposited is 0.8 nm, that is 0.24 THz at the resonance point where wavelength is around 1550 nm. Taking advantage of this conclusion, efficient optical modulation is available by choosing different frequency band resonance wavelengths to narrow the frequency modulation range.
基金Project supported by the Science and Technology Development of Jilin Province(Nos.20110320,201201078)
文摘By using the coupled mode theory and the transfer matrix technique,the optical transfer function is presented for analyzing the size of the waveguide,radius of the microring,free spectral range and amplitude coupling ratio of the vertical coupling microring resonator.Under the central wavelength of 1550 nm,optimization and simulation are performed when the central deviation between the ring and the channel is 0,0.5,1μm,respectively, the 3-dB bandwidth of the spectral response is about 0.21,0.09,0.03 nm,and the intensity of the nonresonant light is below-30,-40,-50 dB,respectively.
基金This study was supported by the National Natural Science Foundation of China (Grant Nos. 61601253 and 6150127 1) and K. C. Wong Magna Fund in Ningbo University.
文摘The microring resonator has received increas- ing attention in the optical sensing application because of its micro-size, optical property, and high sensitivity. An additional waveguide is commonly used to change the output spectra in the early research on microring resonators. In this study, we proposed a nested microring resonator that doubles the free spectral range (FSR) compared with the conventional single microring. This structure improved the sensing property as the FSR in the filter output spectra could be considered as a measurement range in the microring sensor. Moreover, the parameters including the coupling coefficient of the three coupling sections, length of the U-bend waveguide, and effective index of a waveguide were tested and carefully selected to optimize the sensing properties. The relationship between these parameters and the output spectra was demonstrated. With linear sensitivity, the structure has a good potential in sensing application.
文摘We demonstrate a directed optical decoder device consisting of two cascaded microring resonators, which are both modulated through the plasma dispersion effect. The inherent resonance wavelength mismatch between two microring resonators caused by fabrication errors is compensated for by using microheaters that are fabricated on top of the microring resonators. Two electrical signals generated by pulse pattern generators are used to modulate the PIN diodes that are embedded in the device, and the results are presented by optical signals detected at the four output ports of the device. The working wavelength and driving voltages of two MRRs are measured and analyzed by the static response spectra of the device. Dynamic experimental results show that the decoding operation is achieved at a speed of 100 Mbps.
基金Project is supported by the National Natural Science Foundation of China (Grant No. 61804148)the National Key Research and Development Program of China (Grant No. 2018YFB2200202)。
文摘A compact and fabrication friendly polarization demultiplexer(P-DEMUX) is proposed and characterized to enable wavelength-division-multiplexing and polarization-division-multiplexing simultaneously. The proposed structure is composed of a polarization-selective microring resonator in ultrathin waveguide and two bus channels in the silicon nitridesilica-silicon horizontal slot waveguides. In the slot waveguide, the transverse electric(TE) mode propagates through the silicon layer, while the transverse magnetic(TM) mode is confined in the slot region. In the designed ultra-thin waveguide, the TM mode is cut-off. The effective indexes of the TE modes for ultrathin and slot waveguides have comparable values. Thanks for these distinguishing features, the input TE mode can be efficiently filtered through the ultra-thin microring at the resonant wavelength, while the TM mode can directly output from the through port. Simulation results show that the extinction ratio of the proposed P-DEMUX for TE and TM modes are 33.21 dB and 24.97 dB, and the insertion losses are 0.346 dB and 0.324 dB, respectively, at the wavelength of 1551.64 nm. Furthermore, the device shows a broad bandwidth(> 100 nm) for an extinction ratio(ER) of > 20 dB. In addition, the proposed P-DEMUX also has a good fabrication tolerance for the waveguide width variation of-20 nm≤ △w_(g)≤ 20 nm and the microring width variation of -20 nm≤ △w_(r) ≤20 nm for a low insertion loss of < 0.75 dB and low ER of <-18 dB.