We report on the fabrication of the lO-mm-long lithium niobate ridge waveguide and its supercontinuum gen- eration at near-visible wavelengths (around 800hm). The waveguides are fabricated by a combination of MeV co...We report on the fabrication of the lO-mm-long lithium niobate ridge waveguide and its supercontinuum gen- eration at near-visible wavelengths (around 800hm). The waveguides are fabricated by a combination of MeV copper ion implantation followed by wet etching in a proton exchanged lithium niobate planar waveguide. Using a mode-locked Ti:sapphire laser with a central wavelength of 800nm, the generated broadest supereontinuum through the ridge waveguides spans 302 nm (at -30 dB points), from 693 to 995 nm. Temporal coherence proper- ties of the supercontinuum are experimentally studied by a Michelson interferometer and the coherence length of the broadest supercontinuum is measured to be 5.2 μm. Our results offer potential for a compact and integrated supercontinuum source for applications including bio-imaging, spectroscopy and optical communication.展开更多
A 45-channel 100 GHz arrayed waveguide grating(AWG) based on Si nanowire waveguides is designed, simulated and fabricated. Transfer function method is used in the spectrum simulation. The simulated results show that t...A 45-channel 100 GHz arrayed waveguide grating(AWG) based on Si nanowire waveguides is designed, simulated and fabricated. Transfer function method is used in the spectrum simulation. The simulated results show that the central wavelength and channel spacing are 1 562.1 nm and 0.8 nm, respectively, which are in accord with the designed values, and the crosstalk is about-23 dB. The device is fabricated on silicon-on-insulator(SOI) substrate by deep ultraviolet lithography(DUV) and inductively coupled plasma(ICP) etching technologies. The 45-channel 100 GHz AWG exhibits insertion loss of 6.5 dB and crosstalk of-8 dB.展开更多
Deeply etched rib waveguides on silicon on insulator platform were not addressed well in research publications. We have analyzed single mode condition and polarization independence of a deeply etched rib waveguide (D...Deeply etched rib waveguides on silicon on insulator platform were not addressed well in research publications. We have analyzed single mode condition and polarization independence of a deeply etched rib waveguide (DE-RW) structure from biosensing perspective. With this rib structure, an asymmetrically etched integrated optic directional coupler has been numerically modeled to have the same coupling length for quasi- TE and TM modes. The coupling coefficients with the glucose solution as an upper cladding were calculated using a full vector mode solver, and the bulk refractive index sensitivity of the sensor was found as 28.305 × 10^-2/RIU for a fundamental quasi-TE mode.展开更多
1.3-μm 1 × 4 MM1 coupler is designed and fabricated on an InP substrate based on a shallow etched waveguide structure. Tapered input/output waveguides and a bending waveguide design are adopted and applied in th...1.3-μm 1 × 4 MM1 coupler is designed and fabricated on an InP substrate based on a shallow etched waveguide structure. Tapered input/output waveguides and a bending waveguide design are adopted and applied in the device to optimize the performance. The average excess losses of the 1 × 4 MMI coupler per channel are 2.8, 1.7, 2.9, and 2.9 dB, respectively. The smallest excess loss can be lower than 0.5 dB in the 40-nm spectrum bandwidth. The average uniformity between the four channels of the MMI coupler is 1.3 dB, while the smallest uniformity is only 0.4 dB.展开更多
Reactive ion etching(RIE) of LiNbO_3(LN) in SF_6 plasma atmosphere was studied for optimizing the preparation conditions for LN ridge waveguides.The samples to be etched are Ti-diffused LN slab waveguides overlaid...Reactive ion etching(RIE) of LiNbO_3(LN) in SF_6 plasma atmosphere was studied for optimizing the preparation conditions for LN ridge waveguides.The samples to be etched are Ti-diffused LN slab waveguides overlaid with a chromium film mask that has a Mach-Zehnder interferometer(MZI) array pattern.The experimental results indicate that the LN-etching rate(R_(LN)) and the Cr-etching rate(R_(Cr)) as well as the rate ratio R_(LN)/R_(Cr) increase with either increasing the radio-frequency(RF) power at a given SF_6 flow rate or increasing the SF_6 flow rate at a fixed RF power.The maximum values of R_(LN) = 43.2 nm/min and R_(LN)/R_(Cr) = 3.27 were achieved with 300 W RF power and 40 sccm SF_6 flow.When the SF_6 flow rate exceeds 40 sccm,an increase in the flow rate causes the etching rates and the rate ratio to decrease.The scanning electron microscope images of the LN ridge prepared after~20 min etching show that the ridge height is 680 nm and the sidewall slope angle is about 60°.展开更多
基金Supported by the National Natural Science Foundation of China under Grant Nos 61575129 and 11375105the Postdoctoral Science Foundation of China under Grant No 2016M602511+1 种基金the Shenzhen Science and Technology Planning under Grant No JCYJ20160422142912923the State Key Laboratory of Nuclear Physics and Technology,Peking University
文摘We report on the fabrication of the lO-mm-long lithium niobate ridge waveguide and its supercontinuum gen- eration at near-visible wavelengths (around 800hm). The waveguides are fabricated by a combination of MeV copper ion implantation followed by wet etching in a proton exchanged lithium niobate planar waveguide. Using a mode-locked Ti:sapphire laser with a central wavelength of 800nm, the generated broadest supereontinuum through the ridge waveguides spans 302 nm (at -30 dB points), from 693 to 995 nm. Temporal coherence proper- ties of the supercontinuum are experimentally studied by a Michelson interferometer and the coherence length of the broadest supercontinuum is measured to be 5.2 μm. Our results offer potential for a compact and integrated supercontinuum source for applications including bio-imaging, spectroscopy and optical communication.
基金supported by the National High Technology Research and Development Program of China(No.2015AA016902)the National Natural Science Foundation of China(Nos.61435013 and 61405188)
文摘A 45-channel 100 GHz arrayed waveguide grating(AWG) based on Si nanowire waveguides is designed, simulated and fabricated. Transfer function method is used in the spectrum simulation. The simulated results show that the central wavelength and channel spacing are 1 562.1 nm and 0.8 nm, respectively, which are in accord with the designed values, and the crosstalk is about-23 dB. The device is fabricated on silicon-on-insulator(SOI) substrate by deep ultraviolet lithography(DUV) and inductively coupled plasma(ICP) etching technologies. The 45-channel 100 GHz AWG exhibits insertion loss of 6.5 dB and crosstalk of-8 dB.
文摘Deeply etched rib waveguides on silicon on insulator platform were not addressed well in research publications. We have analyzed single mode condition and polarization independence of a deeply etched rib waveguide (DE-RW) structure from biosensing perspective. With this rib structure, an asymmetrically etched integrated optic directional coupler has been numerically modeled to have the same coupling length for quasi- TE and TM modes. The coupling coefficients with the glucose solution as an upper cladding were calculated using a full vector mode solver, and the bulk refractive index sensitivity of the sensor was found as 28.305 × 10^-2/RIU for a fundamental quasi-TE mode.
基金Project supported by the National Natural Science Foundation of China(Nos.61274046,61201103)the National High Technology Research and Development Program of China(No.2013AA014202)
文摘1.3-μm 1 × 4 MM1 coupler is designed and fabricated on an InP substrate based on a shallow etched waveguide structure. Tapered input/output waveguides and a bending waveguide design are adopted and applied in the device to optimize the performance. The average excess losses of the 1 × 4 MMI coupler per channel are 2.8, 1.7, 2.9, and 2.9 dB, respectively. The smallest excess loss can be lower than 0.5 dB in the 40-nm spectrum bandwidth. The average uniformity between the four channels of the MMI coupler is 1.3 dB, while the smallest uniformity is only 0.4 dB.
基金supported by the National Natural Science Foundation of China(No.61078039)
文摘Reactive ion etching(RIE) of LiNbO_3(LN) in SF_6 plasma atmosphere was studied for optimizing the preparation conditions for LN ridge waveguides.The samples to be etched are Ti-diffused LN slab waveguides overlaid with a chromium film mask that has a Mach-Zehnder interferometer(MZI) array pattern.The experimental results indicate that the LN-etching rate(R_(LN)) and the Cr-etching rate(R_(Cr)) as well as the rate ratio R_(LN)/R_(Cr) increase with either increasing the radio-frequency(RF) power at a given SF_6 flow rate or increasing the SF_6 flow rate at a fixed RF power.The maximum values of R_(LN) = 43.2 nm/min and R_(LN)/R_(Cr) = 3.27 were achieved with 300 W RF power and 40 sccm SF_6 flow.When the SF_6 flow rate exceeds 40 sccm,an increase in the flow rate causes the etching rates and the rate ratio to decrease.The scanning electron microscope images of the LN ridge prepared after~20 min etching show that the ridge height is 680 nm and the sidewall slope angle is about 60°.