Electrically controlled optical-mode switch for fundamental mode and first order mode

AbstractRaman spectroscopy is used to characterize silicon implanted with boron at a dose of 1014/cm2 or less and thermally annealed. The Raman scattering strengths and band shapes of the first-order optical mode at 520 cm-1 and of the second-order phonon modes are investigated to determine which modes are sensitive to the boron implant. The asimplanted samples show diminishing Raman scattering strength as the boron dose increases when the incident laser beam is 60° with respect to the sample normal. Thermal annealing restores some of the Raman scattering strength. Three excitation wavelengths are used and the shortest, 457.9 nm, yields the greatest spectral differences from unimplanted silicon. The backscattering geometry shows a variety of changes in the Raman spectrum upon boron implantation. These involve band shifts of the first-order optical mode, bandwidth variations of the first-order optical mode, and the intensity of the second-order mode at 620 cm-1.

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Raman Spectroscopy of Ion-Implanted Silicon

MRS Proceedings ◽

10.1557/proc-439-47 ◽

1996 ◽

Vol 439 ◽

Author(s):

David D. Tuschel ◽

James P. Lavine

Keyword(s):

Raman Spectroscopy ◽

Raman Scattering ◽

Second Order ◽

Order Mode ◽

Optical Mode ◽

Phonon Modes ◽

Incident Laser ◽

First Order ◽

Boron Implantation ◽

Scattering Strength

AbstractRaman spectroscopy is used to characterize silicon implanted with boron at a dose of 1014/cm2 or less and thermally annealed. The Raman scattering strengths and band shapes of the first-order optical mode at 520 cm-1 and of the second-order phonon modes are investigated to determine which modes are sensitive to the boron implant. The asimplanted samples show diminishing Raman scattering strength as the boron dose increases when the incident laser beam is 60° with respect to the sample normal. Thermal annealing restores some of the Raman scattering strength. Three excitation wavelengths are used and the shortest, 457.9 nm, yields the greatest spectral differences from unimplanted silicon. The backscattering geometry shows a variety of changes in the Raman spectrum upon boron implantation. These involve band shifts of the first-order optical mode, bandwidth variations of the first-order optical mode, and the intensity of the second-order mode at 620 cm-1.

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Au Nanoparticles-Doped Polymer All-Optical Switches Based on Photothermal Effects

Polymers ◽

10.3390/polym12091960 ◽

2020 ◽

Vol 12 (9) ◽

pp. 1960 ◽

Cited By ~ 1

Author(s):

Yue Cao ◽

Daming Zhang ◽

Yue Yang ◽

Baizhu Lin ◽

Jiawen Lv ◽

...

Keyword(s):

Power Consumption ◽

Optical Switching ◽

Au Nanoparticles ◽

Optical Switches ◽

Order Mode ◽

Mode Switch ◽

First Order ◽

All Optical ◽

Doped Polymer ◽

All Optical Switching

This article demonstrated the Au nanoparticles-doped polymer all-optical switches based on photothermal effects. The Au nanoparticles have a strong photothermal effect, which would generate the inhomogeneous thermal field distributions in the waveguide under the laser irradiation. Meanwhile, the polymer materials have the characteristics of good compatibility with photothermal materials, low cost, high thermo-optical coefficient and flexibility. Therefore, the Au nanoparticles-doped polymer material can be applied in optically controlled optical switches with low power consumption, small device dimension and high integration. Moreover, the end-pumping method has a higher optical excitation efficiency, which can further reduce the power consumption of the device. Two kinds of all-optical switching devices have been designed including a base mode switch and a first-order mode switch. For the base mode switch, the power consumption and the rise/fall time were 2.05 mW and 17.3/106.9 μs, respectively at the wavelength of 650 nm. For the first-order mode switch, the power consumption and the rise/fall time were 0.5 mW and 10.2/74.9 μs, respectively at the wavelength of 532 nm. This all-optical switching device has the potential applications in all-optical networks, flexibility device and wearable technology fields.

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Optimized offset to eliminate first-order mode excitation at the junction of straight and curved multimode waveguides

IEEE Photonics Technology Letters ◽

10.1109/68.681291 ◽

1998 ◽

Vol 10 (7) ◽

pp. 982-984 ◽

Cited By ~ 5

Author(s):

T. Hirono ◽

M. Kohtoku ◽

Y. Yoshikuni ◽

W.W. Lui ◽

K. Yokoyama

Keyword(s):

Order Mode ◽

First Order ◽

Mode Excitation ◽

Multimode Waveguides

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Centrifuge Model Tests of the Effect of the Ground Motion Coherence Function on the Amplification of a Saturated Soil–Water Site

Geofluids ◽

10.1155/2021/5575433 ◽

2021 ◽

Vol 2021 ◽

pp. 1-10

Author(s):

Xijun Song ◽

Juan Liu ◽

Jingyan Lan ◽

Ting Wang

Keyword(s):

Soil Water ◽

Site Response ◽

Coherence Function ◽

Spectral Ratio ◽

Saturated Soil ◽

Order Mode ◽

Overlying Water ◽

First Order ◽

Site Model ◽

Frequency Phase

Two sets of dynamic centrifugal model tests were designed and implemented in this study: the overlying waterless surface and the water-covered surface. Based on the use of the El Centro waves with different intensities as the base input, the seismic time history at the surface of two sets of free site models was obtained. According to the results of the site response at two sets of the free site surface obtained with a traditional spectral ratio, the coherence functions at the surface and the base were used to modify the traditional spectral ratio for analysis and to evaluate the effect of the ground motion coherence function for site amplification. The modal characteristics and the amplification effect of a typical saturated soil water free site were summarized at the same time. The results showed that the ground response results of the two groups of typical free site centrifugal models were greatly influenced by the coherence function. In the low frequency phase, the coherence function of the amplification spectrum of the site response decreased significantly, while in the high frequency phase, the decrease trend decreased. The coherence function had a significant effect on the first-order mode of the free site. The first-order mode frequency and the amplification factor of a typical free site could be identified effectively. Compared with the saturated land free site model, the saturated soil water free site model had higher-order modes due to the overlying water. It was shown that the overlying water, as part of a complex medium system, could be ignored in the site response and basic cycle estimation.

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first-order mode

Computer Science and Communications Dictionary ◽

10.1007/1-4020-0613-6_7203 ◽

2000 ◽

pp. 611-611

Author(s):

Martin H. Weik

Keyword(s):

Order Mode ◽

First Order

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On-chip optical isolator based on unidirectional wavelength-mode conversion waveguide

Modern Physics Letters B ◽

10.1142/s0217984918502585 ◽

2018 ◽

Vol 32 (22) ◽

pp. 1850258 ◽

Cited By ~ 1

Author(s):

Wenlong Liu ◽

Xuebin Liu ◽

Qiangqiang Yan ◽

Simiao Qiang ◽

Haifeng Pi ◽

...

Keyword(s):

Fundamental Mode ◽

Mode Conversion ◽

Forward Direction ◽

Light Signal ◽

Necessary Condition ◽

Order Mode ◽

Optical Isolator ◽

Silicon Waveguide ◽

Time Space ◽

On Chip

Breaking Lorentz reciprocity is one necessary condition of optical isolator design. Unidirectional wavelength-mode conversion will be realized in a time-dependent system through a short operating range. Based on plasma dispersion effect, generate space-asymmetric periodical time-space modulation on silicon waveguide, and non-reciprocal propagation is realized in the waveguide. The designed unidirectional wavelength-mode conversion waveguide demonstrated that in the forward direction, input 1.55 [Formula: see text]m fundamental mode light signal and then output 1.5492 [Formula: see text]m is of 1st-order mode, while in the backward direction, input 1.5492 [Formula: see text]m is of 1st-order mode light signal and then output 1.5484 [Formula: see text]m is of fundamental mode. Based on this non-reciprocal structure, mode conversion waveguide and two-ring resonance filters were designed then, to accomplish on-chip optical isolation. The scale of the designed isolator is 160 [Formula: see text]m × 60 [Formula: see text]m, and the isolation is 21 dB, revealing perfect application potential.

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