Millimetre-wave(mmWave)technology continues to draw great interest due to its broad applications in wireless communications,radar,and spectroscopy.Compared to pure electronic solutions,photonic-based mmWave generation...Millimetre-wave(mmWave)technology continues to draw great interest due to its broad applications in wireless communications,radar,and spectroscopy.Compared to pure electronic solutions,photonic-based mmWave generation provides wide bandwidth,low power dissipation,and remoting through low-loss fibres.However,at high frequencies,two major challenges exist for the photonic system:the power roll-off of the photodiode,and the large signal linewidth derived directly from the lasers.Here,we demonstrate a new photonic mmWave platform combining integrated microresonator solitons and high-speed photodiodes to address the challenges in both power and coherence.The solitons,being inherently mode-locked,are measured to provide 5.8 dB additional gain through constructive interference among mmWave beatnotes,and the absolute mmWave power approaches the theoretical limit of conventional heterodyne detection at 100 GHz.In our free-running system,the soliton is capable of reducing the mmWave linewidth by two orders of magnitude from that of the pump laser.Our work leverages microresonator solitons and high-speed modified uni-traveling carrier photodiodes to provide a viable path to chip-scale,high-power,low-noise,high-frequency sources for mmWave applications.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
基金The authors thank Ligentec and VLC Photonics for resonator fabrication,S.Bowers at UVA for access to the spearum analyser,and Q.F.Yang at Caltech for helpful comments during the preparation of this manuscript.The authors also gratefully acknowledge the support from the National Science Foundation and Defense Advanced Research Projeas Agency(DARPA)under HR0011-ISC-0055(DODOS).X.Y.is also supported by Virginia Space Grant Consortium.
文摘Millimetre-wave(mmWave)technology continues to draw great interest due to its broad applications in wireless communications,radar,and spectroscopy.Compared to pure electronic solutions,photonic-based mmWave generation provides wide bandwidth,low power dissipation,and remoting through low-loss fibres.However,at high frequencies,two major challenges exist for the photonic system:the power roll-off of the photodiode,and the large signal linewidth derived directly from the lasers.Here,we demonstrate a new photonic mmWave platform combining integrated microresonator solitons and high-speed photodiodes to address the challenges in both power and coherence.The solitons,being inherently mode-locked,are measured to provide 5.8 dB additional gain through constructive interference among mmWave beatnotes,and the absolute mmWave power approaches the theoretical limit of conventional heterodyne detection at 100 GHz.In our free-running system,the soliton is capable of reducing the mmWave linewidth by two orders of magnitude from that of the pump laser.Our work leverages microresonator solitons and high-speed modified uni-traveling carrier photodiodes to provide a viable path to chip-scale,high-power,low-noise,high-frequency sources for mmWave applications.
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.