High-power tunable lasers are intensely pursued due to their vast application potential such as in telecom,ranging,and molecular sensing.Integrated photonics,however,is usually considered not suitable for high-power a...High-power tunable lasers are intensely pursued due to their vast application potential such as in telecom,ranging,and molecular sensing.Integrated photonics,however,is usually considered not suitable for high-power applications mainly due to its small size which limits the energy storage capacity and,therefore,the output power.In the late 90s,to improve the beam quality and increase the stored energy,large-mode-area(LMA)fibers were introduced in which the optical mode area is substantially large.Such LMA fibers have transformed the high-power capability of fiber systems ever since.Introducing such an LMA technology at the chip-scale can play an equally disruptive role with high power signal generation from an integrated photonics system.To this end,in this work we demonstrate such a technology,and show a very high-power tunable laser with the help of a silicon photonics based LMA power amplifier.We show output power reaching 1.8 W over a tunability range of 60 nm,spanning from 1.83μm to 1.89μm,limited only by the seed laser.Such an integrated LMA device can be used to substantially increase the power of the existing integrated tunable lasers currently limited to a few tens of milliwatts.The power levels demonstrated here reach and surpass that of many benchtop systems which truly makes the silicon photonics based integrated LMA device poised towards mass deployment for high power applications without relying on benchtop systems.展开更多
Silicon is well known for its strong third-order optical nonlinearity,exhibiting efficient supercontinuum and four-wave mixing processes.A strong second-order effect that is naturally inhibited in silicon can also be ...Silicon is well known for its strong third-order optical nonlinearity,exhibiting efficient supercontinuum and four-wave mixing processes.A strong second-order effect that is naturally inhibited in silicon can also be observed,for example,by electrically breaking the inversion symmetry and quasi-phase matching the pump and the signal.To generate an efficient broadband second-harmonic signal,however,the most promising technique requires matching the group velocities of the pump and the signal.In this work,we utilize dispersion engineering of a silicon waveguide to achieve group velocity matching between the pump and the signal,along with an additional degree of freedom to broaden the second harmonic through the strong third-order nonlinearity.We demonstrate that the strong self-phase modulation and cross-phase modulation in silicon help broaden the second harmonic by 200 nm in the O-band.Furthermore,we show a waveguide design that can be used to generate a second-harmonic signal in the entire nearinfrared region.Our work paves the way for various applications,such as efficient and broadband complementarymetal oxide semiconductor based on-chip frequency synthesizers,entangled photon pair generators,and optical parametric oscillators.展开更多
Optical frequency synthesizers have widespread applications in optical spectroscopy,frequency metrology,and many other fields.However,their applicability is currently limited by size,cost,and power consumption.Silicon...Optical frequency synthesizers have widespread applications in optical spectroscopy,frequency metrology,and many other fields.However,their applicability is currently limited by size,cost,and power consumption.Silicon photonics technology,which is compatible with complementary-metal-oxide-semiconductor fabrication processes,provides a low-cost,compact size,lightweight,and low-power-consumption solution.In this work,we demonstrate an optical frequency synthesizer using a fully integrated silicon-based tunable laser.The synthesizer can be self-calibrated by tuning the repetition rate of the internal mode-locked laser.A 20 nm tuning range from 1544 to 1564 nm is achieved with~10−13 frequency instability at 10 s averaging time.Its flexibility and fast reconfigurability are also demonstrated by fine tuning the synthesizer and generating arbitrary specified patterns over time-frequency coordinates.This work promotes the frequency stability of silicon-based integrated tunable lasers and paves the way toward chip-scale lowcost optical frequency synthesizers.展开更多
Efficient complementary metal-oxide semiconductor-based nonlinear optical devices in the near-infrared are in strong demand.Due to two-photon absorption in silicon,however,much nonlinear research is shifting towards u...Efficient complementary metal-oxide semiconductor-based nonlinear optical devices in the near-infrared are in strong demand.Due to two-photon absorption in silicon,however,much nonlinear research is shifting towards unconventional photonics platforms.In this work,we demonstrate the generation of an octave-spanning coherent supercontinuum in a silicon waveguide covering the spectral region from the near-to shortwave-infrared.With input pulses of 18 pJ in energy,the generated signal spans the wavelength range from the edge of the silicon transmission window,approximately 1.06 to beyond 2.4μm,with a−20 dB bandwidth covering 1.124–2.4μm.An octave-spanning supercontinuum was also observed at the energy levels as low as 4 pJ(−35 dB bandwidth).We also measured the coherence over an octave,obtaining|g_()12^(1)(λ)>90%,in good agreement with the simulations.In addition,we demonstrate optimization of the third-order dispersion of the waveguide to strengthen the dispersive wave and discuss the advantage of having a soliton at the long wavelength edge of an octave-spanning signal for nonlinear applications.This research paves the way for applications,such as chip-scale precision spectroscopy,optical coherence tomography,optical frequency metrology,frequency synthesis and wide-band wavelength division multiplexing in the telecom window.展开更多
Silicon photonics is coming of age;however,it is still lacking a monolithic platform for optical sources and nonlinear functionalities prompting heterogeneous integration of different materials tailored to different a...Silicon photonics is coming of age;however,it is still lacking a monolithic platform for optical sources and nonlinear functionalities prompting heterogeneous integration of different materials tailored to different applications.Here we demonstrate tellurium oxide as a complementary metal oxide semiconductor silicon photonics platform for nonlinear functionalities,which is already becoming an established platform for sources and amplifiers.We show broadband supercontinuum generation covering the entire telecom window and show for the first time to our knowledge third-harmonic generation in its integrated embodiment.Together with the nowavailable lasers and amplifiers on integrated Te O_(2) this work paves the way for a monolithic TeO_(2)-based nonlinear silicon photonics platform.展开更多
We report the fabrication and characterization of silicon carbide microdisks on top of silicon pillars suited for applications from near-to mid-infrared. We probe 10 μm diameter disks with different under-etching dep...We report the fabrication and characterization of silicon carbide microdisks on top of silicon pillars suited for applications from near-to mid-infrared. We probe 10 μm diameter disks with different under-etching depths,from 4 μm down to 1.4 μm, fabricated by isotropic plasma etching and extract quality factors up to 8400 at telecom wavelength. Our geometry is suited to present high Q single-mode operation. We experimentally demonstrate high-order whispering-gallery mode suppression while preserving the fundamental gallery mode and investigate some requirements for nonlinear optics applications on this platform, specifically in terms of quality factor and dispersion for Kerr frequency comb generation.展开更多
基金supported by EU Horizon 2020 Framework Programme—Grant Agreement No.:965124(FEMTOCHIP)Deutsche Forschungsgemeinschaft(SP2111)contract number PACE:Ka908/10-1Open Access funding enabled and organized by Projekt DEAL.
文摘High-power tunable lasers are intensely pursued due to their vast application potential such as in telecom,ranging,and molecular sensing.Integrated photonics,however,is usually considered not suitable for high-power applications mainly due to its small size which limits the energy storage capacity and,therefore,the output power.In the late 90s,to improve the beam quality and increase the stored energy,large-mode-area(LMA)fibers were introduced in which the optical mode area is substantially large.Such LMA fibers have transformed the high-power capability of fiber systems ever since.Introducing such an LMA technology at the chip-scale can play an equally disruptive role with high power signal generation from an integrated photonics system.To this end,in this work we demonstrate such a technology,and show a very high-power tunable laser with the help of a silicon photonics based LMA power amplifier.We show output power reaching 1.8 W over a tunability range of 60 nm,spanning from 1.83μm to 1.89μm,limited only by the seed laser.Such an integrated LMA device can be used to substantially increase the power of the existing integrated tunable lasers currently limited to a few tens of milliwatts.The power levels demonstrated here reach and surpass that of many benchtop systems which truly makes the silicon photonics based integrated LMA device poised towards mass deployment for high power applications without relying on benchtop systems.
基金supported by the Defense Advanced Research Projects Agency(DARPA)under the Direct-on-chip digital optical synthesizer(DODOS)project-contract number HR0011-15-C-0056.
文摘Silicon is well known for its strong third-order optical nonlinearity,exhibiting efficient supercontinuum and four-wave mixing processes.A strong second-order effect that is naturally inhibited in silicon can also be observed,for example,by electrically breaking the inversion symmetry and quasi-phase matching the pump and the signal.To generate an efficient broadband second-harmonic signal,however,the most promising technique requires matching the group velocities of the pump and the signal.In this work,we utilize dispersion engineering of a silicon waveguide to achieve group velocity matching between the pump and the signal,along with an additional degree of freedom to broaden the second harmonic through the strong third-order nonlinearity.We demonstrate that the strong self-phase modulation and cross-phase modulation in silicon help broaden the second harmonic by 200 nm in the O-band.Furthermore,we show a waveguide design that can be used to generate a second-harmonic signal in the entire nearinfrared region.Our work paves the way for various applications,such as efficient and broadband complementarymetal oxide semiconductor based on-chip frequency synthesizers,entangled photon pair generators,and optical parametric oscillators.
基金financial support by the Defense Advanced Research Projects Agency(DARPA)Direct On-Chip Digital Optical Synthesizer(DODOS)project(HR0011-15-C-0056,program manager:Dr.Gordon Keeler)the Deutsche Forschungsgemeinschaft through Priority Program SPP-1221,DFG 18-17 PACE+1 种基金the Deutsches Elektronen Synchrotron-DESYsupported by a National Science Scholarship(NSS)from the Agency for Science,Technology and Research(A*STAR),Singapore.
文摘Optical frequency synthesizers have widespread applications in optical spectroscopy,frequency metrology,and many other fields.However,their applicability is currently limited by size,cost,and power consumption.Silicon photonics technology,which is compatible with complementary-metal-oxide-semiconductor fabrication processes,provides a low-cost,compact size,lightweight,and low-power-consumption solution.In this work,we demonstrate an optical frequency synthesizer using a fully integrated silicon-based tunable laser.The synthesizer can be self-calibrated by tuning the repetition rate of the internal mode-locked laser.A 20 nm tuning range from 1544 to 1564 nm is achieved with~10−13 frequency instability at 10 s averaging time.Its flexibility and fast reconfigurability are also demonstrated by fine tuning the synthesizer and generating arbitrary specified patterns over time-frequency coordinates.This work promotes the frequency stability of silicon-based integrated tunable lasers and paves the way toward chip-scale lowcost optical frequency synthesizers.
基金supported by Defense Advanced Research Projects Agency(DARPA)under the Direct on-chip digital optical synthesizer(DODOS)project-contract number HR0011-15-C-0056the NSS fellowship from Agency of Science,Technology,and Research(A*STAR),Singapore.
文摘Efficient complementary metal-oxide semiconductor-based nonlinear optical devices in the near-infrared are in strong demand.Due to two-photon absorption in silicon,however,much nonlinear research is shifting towards unconventional photonics platforms.In this work,we demonstrate the generation of an octave-spanning coherent supercontinuum in a silicon waveguide covering the spectral region from the near-to shortwave-infrared.With input pulses of 18 pJ in energy,the generated signal spans the wavelength range from the edge of the silicon transmission window,approximately 1.06 to beyond 2.4μm,with a−20 dB bandwidth covering 1.124–2.4μm.An octave-spanning supercontinuum was also observed at the energy levels as low as 4 pJ(−35 dB bandwidth).We also measured the coherence over an octave,obtaining|g_()12^(1)(λ)>90%,in good agreement with the simulations.In addition,we demonstrate optimization of the third-order dispersion of the waveguide to strengthen the dispersive wave and discuss the advantage of having a soliton at the long wavelength edge of an octave-spanning signal for nonlinear applications.This research paves the way for applications,such as chip-scale precision spectroscopy,optical coherence tomography,optical frequency metrology,frequency synthesis and wide-band wavelength division multiplexing in the telecom window.
基金Defense Advanced Research Projects Agency(HR0011-15-C-0056)Natural Sciences and Engineering Research Council of Canada(RGPIN-2017-06423,STPGP 494306)Deutsche Forschungsgemeinschaft(SP2111).
文摘Silicon photonics is coming of age;however,it is still lacking a monolithic platform for optical sources and nonlinear functionalities prompting heterogeneous integration of different materials tailored to different applications.Here we demonstrate tellurium oxide as a complementary metal oxide semiconductor silicon photonics platform for nonlinear functionalities,which is already becoming an established platform for sources and amplifiers.We show broadband supercontinuum generation covering the entire telecom window and show for the first time to our knowledge third-harmonic generation in its integrated embodiment.Together with the nowavailable lasers and amplifiers on integrated Te O_(2) this work paves the way for a monolithic TeO_(2)-based nonlinear silicon photonics platform.
基金Agence Nationale de la Recherche(ANR)(MIRSICOMB ANR-17-CE24-0028)FP7 People:Marie-Curie Actions(PEOPLE)(PCIGA-2013-631543)
文摘We report the fabrication and characterization of silicon carbide microdisks on top of silicon pillars suited for applications from near-to mid-infrared. We probe 10 μm diameter disks with different under-etching depths,from 4 μm down to 1.4 μm, fabricated by isotropic plasma etching and extract quality factors up to 8400 at telecom wavelength. Our geometry is suited to present high Q single-mode operation. We experimentally demonstrate high-order whispering-gallery mode suppression while preserving the fundamental gallery mode and investigate some requirements for nonlinear optics applications on this platform, specifically in terms of quality factor and dispersion for Kerr frequency comb generation.
