A low noise oscillator is a crucial component in determining system performance in modern communication,microwave spectroscopy,microwave-based sensing(including radar and remote sensing),and metrology systems.In recen...A low noise oscillator is a crucial component in determining system performance in modern communication,microwave spectroscopy,microwave-based sensing(including radar and remote sensing),and metrology systems.In recent years,ultra-low phase noise photonic microwave oscillators based on optical frequency division have become a paradigm shift for the generation of high performance microwave signals.In this work,we report on-chip low phase noise photonic microwave generation based on spiral resonator referenced lasers and an integrated electro-optical frequency comb.Dual lasers are co-locked to an ultra-high-Q silicon nitride spiral resonator and their relative phase noise is measured below the cavity thermal noise limit,resulting in record low onchip optical phase noise.A broadband integrated electro-optic frequency comb is utilized to divide down the relative phase noise of the spiral resonator referenced lasers to the microwave domain,resulting in recordlow phase noise for chip-based oscillators(-69 d Bc∕Hz at 10 Hz offset,and-144 d Bc∕Hz at 10 k Hz offset for a 10 GHz carrier scaled from 37.3 GHz output).The exceptional phase noise performance,planar chip design,high technology readiness level,and foundry-ready processing of the current work represent a major advance of integrated photonic microwave oscillators.展开更多
Kerr soliton microcombs have the potential to disrupt a variety of applications such as ultra-high-speed optical communications,ultra-fast distance measurements,massively parallel light detection and ranging(LiDAR)or ...Kerr soliton microcombs have the potential to disrupt a variety of applications such as ultra-high-speed optical communications,ultra-fast distance measurements,massively parallel light detection and ranging(LiDAR)or high-resolution optical spectroscopy.Similarly,ultra-broadband photonic-electronic signal processing could also benefit from chip-scale frequency comb sources that offer wideband optical emission along with ultra-low phase noise and timing jitter.However,while photonic analogue-to-digital converters(ADC)based on femtosecond lasers have been shown to overcome the jitter-related limitations of electronic oscillators,the potential of Kerr combs in photonic-electronic signal processing remains to be explored.In this work,we demonstrate a microcomb-based photonic-electronic ADC that combines a high-speed electro-optic modulator with a Kerr comb for spectrally sliced coherent detection of the generated optical waveform.The system offers a record-high acquisition bandwidth of 320 GHz,corresponding to an effective sampling rate of at least 640GSa/s.In a proof-of-concept experiment,we demonstrate the viability of the concept by acquiring a broadband analogue data signal comprising different channels with centre frequencies between 24 GHz and 264 GHz,offering bit error ratios(BER)below widely used forward-error-correction(FEC)thresholds.To the best of our knowledge,this is the first demonstration of a microcomb-based ADC,leading to the largest acquisition bandwidth demonstrated for any ADC so far.展开更多
The recent advancement in lithium-niobite-on-insulator(LNOI)technology is opening up new opportunities in optoelectronics,as devices with better performance,lower power consumption and a smaller footprint can be reali...The recent advancement in lithium-niobite-on-insulator(LNOI)technology is opening up new opportunities in optoelectronics,as devices with better performance,lower power consumption and a smaller footprint can be realised due to the high optical confinement in the structures.The LNOI platform offers both largeχ(2)andχ(3)nonlinearities along with the power of dispersion engineering,enabling brand new nonlinear photonic devices and applications for the next generation of integrated photonic circuits.However,Raman scattering and its interaction with other nonlinear processes have not been extensively studied in dispersion-engineered LNOI nanodevices.In this work,we characterise the Raman radiation spectra in a monolithic lithium niobate(LN)microresonator via selective excitation of Raman-active phonon modes.The dominant mode for the Raman oscillation is observed in the backward direction for a continuous-wave pump threshold power of 20mW with a high differential quantum efficiency of 46%.We explore the effects of Raman scattering on Kerr optical frequency comb generation.We achieve mode-locked states in an X-cut LNOI chip through sufficient suppression of the Raman effect via cavity geometry control.Our analysis of the Raman effect provides guidance for the development of future chip-based photonic devices on the LNOI platform.展开更多
Lithium niobate on insulator(LNOI)has become an intriguing platform for integrated photonics for applications in communications,microwave photonics,and computing.Whereas,integrated devices including modulators,resonat...Lithium niobate on insulator(LNOI)has become an intriguing platform for integrated photonics for applications in communications,microwave photonics,and computing.Whereas,integrated devices including modulators,resonators,and lasers with high performance have been recently realized on the LNOI platform,high-speed photodetectors,an essential building block in photonic integrated circuits,have not been demonstrated on LNOI yet.Here,we demonstrate for the first time,heterogeneously integrated modified uni-traveling carrier photodiodes on LNOI with a record-high bandwidth of 80 GHz and a responsivity of 0.6 A/W at a 1550-nm wavelength.The photodiodes are based on an n-down In GaAs/InP epitaxial layer structure that was optimized for high carrier transit time-limited bandwidth.Photodiode integration was achieved using a scalable wafer die bonding approach that is fully compatible with the LNOI platform.展开更多
Manipulating the frequency and bandwidth of nonclassical light is essential for implementing frequency-encoded/multiplexed quantum computation,communication,and networking protocols,and for bridging spectral mismatch ...Manipulating the frequency and bandwidth of nonclassical light is essential for implementing frequency-encoded/multiplexed quantum computation,communication,and networking protocols,and for bridging spectral mismatch among various quantum systems.However,quantum spectral control requires a strong nonlinearity mediated by light,microwave,or acoustics,which is challenging to realize with high efficiency,low noise,and on an integrated chip.Here,we demonstrate both frequency shifting and bandwidth compression of heralded single-photon pulses using an integrated thin-film lithium niobate(TFLN)phase modulator.We achieve record-high electro-optic frequency shearing of telecom single photons over terahertz range(±641 GHz or±5.2 nm),enabling high visibility quantum interference between frequency-nondegenerate photon pairs.We further operate the modulator as a time lens and demonstrate over eighteen-fold(6.55 nm to 0.35 nm)bandwidth compression of single photons.Our results showcase the viability and promise of on-chip quantum spectral control for scalable photonic quantum information processing.展开更多
基金Defense Advanced Research Projects Agency(HR001122C0019)。
文摘A low noise oscillator is a crucial component in determining system performance in modern communication,microwave spectroscopy,microwave-based sensing(including radar and remote sensing),and metrology systems.In recent years,ultra-low phase noise photonic microwave oscillators based on optical frequency division have become a paradigm shift for the generation of high performance microwave signals.In this work,we report on-chip low phase noise photonic microwave generation based on spiral resonator referenced lasers and an integrated electro-optical frequency comb.Dual lasers are co-locked to an ultra-high-Q silicon nitride spiral resonator and their relative phase noise is measured below the cavity thermal noise limit,resulting in record low onchip optical phase noise.A broadband integrated electro-optic frequency comb is utilized to divide down the relative phase noise of the spiral resonator referenced lasers to the microwave domain,resulting in recordlow phase noise for chip-based oscillators(-69 d Bc∕Hz at 10 Hz offset,and-144 d Bc∕Hz at 10 k Hz offset for a 10 GHz carrier scaled from 37.3 GHz output).The exceptional phase noise performance,planar chip design,high technology readiness level,and foundry-ready processing of the current work represent a major advance of integrated photonic microwave oscillators.
基金supported by the ERC Consolidator Grant TeraSHAPE(#773248)the H2020 project TeraSlice(#863322)+10 种基金by the EIC Transition projects MAGNIFY(#101113302),HDLN(#101113260),and CombTools(#101136978)by the H2020 Marie Skłodowska-Curie Innovative Training Network“MICROCOMB”(#812818)by the Deutsche Forschungsgemeinschaft(DFG)project PACE(#403188360)within the Priority Programme“Electronic-Photonic Integrated Systems for Ultrafast Signal Processing”(SPP 2111)by the DFG Collaborative Research Centre(CRC)WavePhenomena(SFB 1173,Project-ID 258734477)by the BMBF project Open6GHub(#16KISK010)by the Alfried Krupp von Bohlen und Halbach-Stiftungby the Max-Planck School of Photonics(MPSP)by the European Regional Development Fund(ERDF,grant EFRE/FEIH_776267)the Deutsche Forschungsgemeinschaft(DFGgrants DFG/INST 121384/166-1 and DFG/INST 121384/167-1The Si3N4 samples were fabricated in the Centre of MicroNano Technology(CMi)at EPFL.
文摘Kerr soliton microcombs have the potential to disrupt a variety of applications such as ultra-high-speed optical communications,ultra-fast distance measurements,massively parallel light detection and ranging(LiDAR)or high-resolution optical spectroscopy.Similarly,ultra-broadband photonic-electronic signal processing could also benefit from chip-scale frequency comb sources that offer wideband optical emission along with ultra-low phase noise and timing jitter.However,while photonic analogue-to-digital converters(ADC)based on femtosecond lasers have been shown to overcome the jitter-related limitations of electronic oscillators,the potential of Kerr combs in photonic-electronic signal processing remains to be explored.In this work,we demonstrate a microcomb-based photonic-electronic ADC that combines a high-speed electro-optic modulator with a Kerr comb for spectrally sliced coherent detection of the generated optical waveform.The system offers a record-high acquisition bandwidth of 320 GHz,corresponding to an effective sampling rate of at least 640GSa/s.In a proof-of-concept experiment,we demonstrate the viability of the concept by acquiring a broadband analogue data signal comprising different channels with centre frequencies between 24 GHz and 264 GHz,offering bit error ratios(BER)below widely used forward-error-correction(FEC)thresholds.To the best of our knowledge,this is the first demonstration of a microcomb-based ADC,leading to the largest acquisition bandwidth demonstrated for any ADC so far.
基金supported by the National Science Foundation under NSF ECCS award No.1541959supported by the National Science Foundation(NSF)(ECCS-1740296 E2CDA)+1 种基金Defense Advanced Research Projects Agency(DARPA)(W31P4Q-15-1-0013)Air Force Office of Scientific Research(AFOSR)(FA9550-15-1-0303).
文摘The recent advancement in lithium-niobite-on-insulator(LNOI)technology is opening up new opportunities in optoelectronics,as devices with better performance,lower power consumption and a smaller footprint can be realised due to the high optical confinement in the structures.The LNOI platform offers both largeχ(2)andχ(3)nonlinearities along with the power of dispersion engineering,enabling brand new nonlinear photonic devices and applications for the next generation of integrated photonic circuits.However,Raman scattering and its interaction with other nonlinear processes have not been extensively studied in dispersion-engineered LNOI nanodevices.In this work,we characterise the Raman radiation spectra in a monolithic lithium niobate(LN)microresonator via selective excitation of Raman-active phonon modes.The dominant mode for the Raman oscillation is observed in the backward direction for a continuous-wave pump threshold power of 20mW with a high differential quantum efficiency of 46%.We explore the effects of Raman scattering on Kerr optical frequency comb generation.We achieve mode-locked states in an X-cut LNOI chip through sufficient suppression of the Raman effect via cavity geometry control.Our analysis of the Raman effect provides guidance for the development of future chip-based photonic devices on the LNOI platform.
基金National Science Foundation(2023775)Air Force Office of Scientific Research(FA 9550-17-1-0071)Defense Advanced Research Projects Agency(HR0011-20-C-0137)。
文摘Lithium niobate on insulator(LNOI)has become an intriguing platform for integrated photonics for applications in communications,microwave photonics,and computing.Whereas,integrated devices including modulators,resonators,and lasers with high performance have been recently realized on the LNOI platform,high-speed photodetectors,an essential building block in photonic integrated circuits,have not been demonstrated on LNOI yet.Here,we demonstrate for the first time,heterogeneously integrated modified uni-traveling carrier photodiodes on LNOI with a record-high bandwidth of 80 GHz and a responsivity of 0.6 A/W at a 1550-nm wavelength.The photodiodes are based on an n-down In GaAs/InP epitaxial layer structure that was optimized for high carrier transit time-limited bandwidth.Photodiode integration was achieved using a scalable wafer die bonding approach that is fully compatible with the LNOI platform.
基金supported by Harvard Quantum Initiative(HQI),ARO/DARPA(W911NF2010248),AFOSR(FA9550-20-1-01015),DARPA LUMOS(HR0011-20-C-0137),DOE(DE-SC0020376),NSF(EEC-1941583,ECCS-1839197),and AFRL(FA9550-21-1-0056)support by HQI post-doctoral fellowship and A*STAR SERC Central Research Fund(CRF)support by the AQT Intelligent Quantum Networks and Technologies(INQNET)research program.
文摘Manipulating the frequency and bandwidth of nonclassical light is essential for implementing frequency-encoded/multiplexed quantum computation,communication,and networking protocols,and for bridging spectral mismatch among various quantum systems.However,quantum spectral control requires a strong nonlinearity mediated by light,microwave,or acoustics,which is challenging to realize with high efficiency,low noise,and on an integrated chip.Here,we demonstrate both frequency shifting and bandwidth compression of heralded single-photon pulses using an integrated thin-film lithium niobate(TFLN)phase modulator.We achieve record-high electro-optic frequency shearing of telecom single photons over terahertz range(±641 GHz or±5.2 nm),enabling high visibility quantum interference between frequency-nondegenerate photon pairs.We further operate the modulator as a time lens and demonstrate over eighteen-fold(6.55 nm to 0.35 nm)bandwidth compression of single photons.Our results showcase the viability and promise of on-chip quantum spectral control for scalable photonic quantum information processing.
