Polymeric Thermo-optic Switch Research Articles

1 × 2 mode-independent polymeric thermo-optic switch based on a Mach-Zehnder interferometer with a multimode interferometer.

We present the design and performances of a broadband 1 × 2 mode-independent thermo-optic (TO) switch based on Mach-Zehnder interferometer (MZI) with multimode interferometer (MMI). The MZI adopts a Y-branch structure as the 3-dB power splitter and a MMI as the coupler, which are designed to be insensitive to the guided modes. By optimizing the structural parameters of the waveguides, mode-independent transmission and switching functions for E11 and E12 modes can be implemented in the C + L band, and the mode content of the outputs is the same as the mode content of the inputs. We proved the working principle of our design based on polymer platform, which was fabricated by using ultraviolet lithography and wet-etching methods. The transmission characteristics for E11 and E12 modes were also analyzed. With the driving power of 5.9 mW, the measured extinction ratios of the switch for E11 and E12 modes are larger than 13.3 dB and 13.1 dB, respectively, over a wavelength range of 1530 nm to 1610 nm. The insertion losses of the device are 11.7 dB and 14.2 dB for E11 and E12 modes, respectively, at 1550 nm wavelength. The switching times of the device are less than 840 µs. The presented mode-independent switch can be applied in reconfigurable mode-division multiplexing systems.

Fabrication of chromophore molecule-linked azo polymer as waveguide material of polymeric thermo-optic digital optical switch

A chromophore molecule-linked azo polymer as waveguide material (MCAP) of polymeric thermo-optic digital optical switch (DOS) was prepared with a chromophore molecule (ABFA), a polyether polyol and isophorone diisocyanate (IPDI). The chemical structures of ABFA monomer and azo polymer MCAP were characterized by FT-IR and UV–Visible spectroscopy. The thermal and mechanical properties of the MCAP film were investigated. The refractive index and transmission loss of MCAP film were measured at different temperatures and different laser wavelengths by an attenuated total reflection (ATR) technique and CCD digital imaging devices. A polymeric thermo-optic DOS based on the thermo-optic effect of the MCAP was designed and the performance of the switch was simulated by using the finite difference beam propagation method (FD-BPM). The experimental results showed that the power consumption of the polymeric thermo-optic switch could be only 0.64[Formula: see text]mW, while the response time of the switch could be as short as 3.0[Formula: see text]ms.

Synthesis of Amino-Functionalized Graphene Oxide/Azobenzene Polyimide and its Simulation of Optical Switches

Abstract In this work, an amino-functionalized graphene oxide (AFGO) was synthesized by graphene oxide (GO) and ethylene diamine. A novel amino-functionalized graphene oxide/azobenzene polyimide (AFGO/ACPI) was synthesized with AFGO, azobenzene chromophore and pyromellitic dianhydride (PMDA). The structure, mechanical and thermal property of AFGO/ACPI were characterized and measured by fourier transform infrared, UV-visible spectroscopy, near-infrared spectrum, thermogravimetric analysis and differential scanning calorimetry. To obtain the refractive index of AFGO/ACPI at different temperature and wavelength (532 nm, 650 nm and 850 nm), the attenuated total reflection (ATR) method was used to measure, and thermo optic coefficients (dn/dT) were −7.22×10−4 (532 nm), −6.20×10−4 (650 nm) and −5.84×10−4 (850 nm) °C−1, respectively. The transmission loss of AFGO/ACPI thin film was surveyed using the CCD digital imaging devices and the value was 0.167 dB/cm. According to the thermo-optic effect of AFGO/ACPI film, the 1×2 Y-branch and 2×2 Mach-Zehnder optical switches were simulated. The results showed that the power consumptions of the 1×2 Y-branch and 2×2 Mach-Zehnder optical switches were only 0.63 mW and 1.45 mW. The response time was about 0.5 ms, and compared to the normal polymeric thermo-optic switch, it can improve the response time and contribute to researches of optical switches.

Noval chiral azobenzene-containing polyurethanes: synthesis, optical properties and simulation comparison of two kind of polymeric thermo-optic switches

In this work, three different structures of chiral side-chain azo polyurethane (CAPU-1), chiral graft azo polyurethane (CAPU-2) and chiral disazo polyurethane (CAPU-3) were synthesized by diazo coupling reaction. The structures of the synthesized compounds of CAPU-1 ~ 3 were measured by FT-IR and UV-Vis spectroscopy. The thermal and mechanical properties of CAPU-1 ~ 3 were investigated. The refractive index (n) and transmission loss of CAPU-1 ~ 3 was measured by ATR technique and CCD digital imaging devices. The Y-branch and Mach–Zehnder polymeric thermo-optic switches were simulated based on the synthesized three chiral azo polyurethanes as waveguide materials. The results demonstrate that the thermo-optic coefficients (dn/dT) of CAPU-1 are −7.21 × 10−4 °C−1 (532 nm), −8.01 × 10–4 °C−1 (650 nm) and −8.34 × 10–4 °C−1 (850 nm); CAPU-2 are −6.39 × 10–4 °C−1 (532 nm), −7.83 × 10–4 °C−1 (650 nm) and −8.71 × 10–4 °C−1 (850 nm); CAPU-3 are −8.22 × 10–4 °C−1 (532 nm), −8.74 × 10–4 °C−1 (650 nm) and −9.78 × 10–4 °C−1 (850 nm), respectively. The transmission losses of CAPU-1 ~ 3 are 0.1816 dB/cm, 0.1908 dB/cm and 0.1705 dB/cm, respectively. The response times of the Y-branch thermo-optic switch of CAPU-1 ~ 3 are 4 ms, 18 ms and 18 ms, respectively; and the response times of the Mach–Zehnder polymeric thermo-optic switch of CAPU-1 ~ 3 are 0.8 ms, 4 ms and 4 ms, respectively. The significant differences in performance are owing to the different substituents and structure of the azo compound. The conclusion had potential significance to improve and develop the new digital optical and thermo-optic switch with short response time and low driving power.

Novel three chiral azobenzene polyurethanes: Preparation, optical properties and simulation comparisons of two different polymeric thermo-optic switches

Three different structures of chiral side-chain azobenzene polyurethane (CAPU-1), chiral graft azobenzene polyurethane (CAPU-2) and chiral bisazo polyurethane (CAPU-3) were prepared by diazo coupling reaction. The structures, thermal, mechanical properties, refractive index (n) and transmission loss of CAPU-1~3 were investigated. The Y-branch and Mach–Zehnder polymeric thermo-optic switches were simulated based on the synthesized three chiral azo polyurethanes as waveguide materials. The response time differences are owing to the different substituents and structure of the azo compound. The conclusion had potential significance to improve and develop the new digital optical and thermo-optic switch (TOS) with short response time and low driving power.

650-nm 1 × 2 polymeric thermo-optic switch with low power consumption.

In this paper, a low-power 1 × 2 polymeric thermo-optic switch operating at the polymer optical fiber low-loss window of 650 nm was studied. The characteristic parameters of the switch were carefully designed and simulated. The fabrication was done by using standard semiconductor fabrication techniques such as spin-coating, photolithography, and dry etching. The device was fabricated based on poly(methyl methacrylate) (PMMA)-based materials with the Mach-Zehnder interferometer (MZI) structure. The device shows an extinction ratio of over 23.4 dB at 650 nm with a very low-power consumption of 5.3 mW. The measured switching rise time and fall time are 464.4 and 448.0 µs, respectively.

Synthesis, Thermo-Optic Properties, and Polymeric Thermo-Optic Switch Based on Novel Optically Active Polyurethane (Urea)

A novel optically active polyurethane (urea) (PUUS) was synthesized based on azo chromophore molecule, 4-(4′-nitro-phenyldiazoalkenyl)-(α-methyl)-benzylamine (NPMBS), S(-)-α-methyl benzylamine, IPDI and GE-210. The physical properties of PUUS were investigated. The refractive index (n), thermo-optic coefficient (dn/dT), transmission loss, dispersions curve and Sellmeyer coefficients of PUUS were obtained by attenuated total reflection technique, charge coupled device and Sellmeyer equation. A Y-branched switch based on thermo-optic effect in the silicon substrate was proposed and the performance of switch was simulated. The power consumption and response time of the thermo-optic switch were only 0.72 mW and 3.5 ms, respectively.

Synthesis, Optical Property, and Simulation of Thermo-Optic Switch of Novel Azopolymer

A novel azopolymer polyurethane-urea (PUU) was synthesized from chromophore molecule 4-(4-nitrophenyl-alkenyl) phenyl-1,3-diamine, polyether polyol, and isophorone diisocyanate. The structure, mechanical property, and thermal property of PUU were characterized and measured. The refractive index and transmission loss of PUU was determined using ATR technique. A Y-branch polymeric thermo-optic switch was proposed and simulated. The result showed that the power consumption of the switch could be only 2.4 mW, and the response time of the switch could reach about 4 ms. It has a significant improvement in reducing the power consumption and response time of the Y-branch polymeric thermo-optic switches.

Synthesis of azo benzothiazole polymer and its application of 1 × 2 Y-branched and 2 × 2 Mach–Zehnder interferometer switch

The azo benzothiazole polyurethane–urea (ABPUU) was synthesized from chromophore molecule 4-[(6-nitrobenzothiazole-2-yl)diazenyl]phenyl-1,3-diamine NBDPD, polyether polyol (NJ-210) and isophorone diisocyanate (IPDI). The structure, thermal property, mechanical property and physical property were characterized and investigated. The refractive index (n) and thermo-optic coefficient (dn/dT) of ABPUU was determined at different temperature and wavelength (532nm, 650nm and 850nm) using attenuated total reflection (ATR) technique. Using the CCD digital imaging devices, transmission loss of ABPUU was measured. A 1×2 Y-branched and 2×2 Mach–Zehnder interferometer (MZI) switch with two rib waveguides, dual driving electrodes and two critical 3-dB couplers polymeric thermo-optic switches based on thermo-optic effect of prepared ABPUU were designed and simulation. The power consumption of the Y-branched switch is less than 0.84mW. The Y-branched and MZI switching rising and falling times obtained are 0.8ms and 0.2ms, respectively.

Preparation, thermo-optic property and simulation of optical switch based on azo benzothiazole polymer

An azo chromophore molecule 4-[(benzothiazole-2-yl)diazenyl]phenyl-1,3-diamine (BTPD) was prepared with 2-amino benzothiazole and m-phenylenediamine by diazo-coupling reaction. Then, the chromophore molecule BTPD was polymerized with NJ-210 and isophorone diisocyanate (IPDI) to obtain novel azo benzothiazole polymer (BTPU). The structures of BTPD and BTPU were characterized using the Fourier transform infrared, UV–visible spectroscopy, DSC and TGA. The physical properties of the obtained BTPU were investigated. The refractive index (n) of BTPU was demonstrated at different temperature and wavelength (532, 650 and 850 nm) using attenuated total reflection technique. The transmission loss and dispersion characteristic of BTPU film were investigated using the CCD digital imaging devices and Sellmeyer equation. A Y-branch and 2 × 2 Mach–Zehnder interferometer (MZI) polymeric thermo-optic switches based on the thermo-optic effect of prepared BTPU were proposed and the performance of switches was simulated. The results indicated that the power consumption of the Y-branch thermo-optic switch could be only 0.6 mW. The Y-branch and MZI switching rising and falling times obtained were 8.0 and 1.8 ms.

Helical Biphenyl Bisazo Polyurethane: Preparation, Characterization and Analysis of Polymeric Thermo-Optic Switch

The bisazo chromophore molecule (CAAPM) and helical biphenyl bisazo polyurethane (HBBPU) were synthesized. The structures of CAAPM and HBBPU were characterized by FT-IR and UV-vis spectroscopic techniques. The measurements of refractive index and thermo-optic coefficient (dn/dT) of HBBPU were demonstrated at different wavelengths and different temperatures by the ATR technique. By using CCD digital imaging devices, transmission loss of the internal waveguide was measured. The refractive index dispersions and Sellmeyer coefficients of HBBPU were obtained by the Sellmeyer equation. A Y-branched switch based on the thermo-optic effect was proposed and the performance of the switch was simulated. With a branching angle of 0.143° and the FD-BPM method, the result showed that the power consumption of the thermo-optic switch could be only 3.6 mW, and the response time of the switch could reach about 8 ms. This is a significant improvement in reducing power consumption compared with the normal Y-branched polymer thermo-optic switch.

Preparation of helical biphenyl polyurethane and its low power consumption thermo-optic switch

Azo chromophore molecule (NDPD) and helical biphenyl polyurethane (HBPU) were prepared. The chemical structures of NDPD and HBPU were characterized by FTIR and UV–vis spectroscopy. The measurements of refractive index, thermo-optic coefficient (dn/dT), transmission loss, refractive index dispersions and Sellmeyer coefficients of HBPU were measured using ATR technique, CCD digital imaging devices and Sellmeyer equation. The results showed that HBPU would be useful for the design of high performance digital optical switch. The prepared HBPU was utilized as core material to propose a Y-branch thermo-optic switch, which was based on thermo-optic effect of HBPU at the infrared communication wavelength of 1.55μm. With branching angle of 0.143° and the finite difference beam propagation method (FD-BPM), the polymeric thermo-optic switch was simulated. The simulation results indicated that the device has a low switching power of 1.68mW and a switching response time of 7.0ms.

Preparation, optical properties and 1 × 2 polymeric thermo-optic switch of polyurethane-urea

A polyurethane-urea (PUU) containing azo chromophore, polyether polyol (NJ-220) and isophorone diisocyanate (IPDI) was prepared. The structure, thermal property and mechanical properties of obtained PUU were characterized and measured by the UV–visible spectroscopy, Fourier transform infrared, Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The refractive index (n) of PUU was determined at different temperature and wavelength (532 nm, 650 nm and 850 nm) using attenuated total reflection (ATR) technique, and the thermo-optic coefficients (dn/dT) were −5.3643 × 10−4 °C−1, −5.2500 × 10−4 °C−1 and −4.6071 × 10−4 °C−1, respectively. Using the Charge Coupled Device (CCD) digital imaging devices, transmission loss of PUU was measured and the value was 0.659 dB cm−1. A 1 × 2 polymeric thermo-optic switch based on the thermo-optic effect of PUU film was proposed. With branching angle of 0.143° and the finite difference beam propagation method (FD-BPM), the polymeric thermo-optic switch was simulated. The result showed that the power consumption of the thermo-optic switch could be only 0.72 mW, and the response time of the switch was about 3.0 ms. The obtained PUU has a significant improvement in reducing the power consumption and response time compared with those of the normal polymeric thermo-optic switches.

Chiral Azo polyurethane(urea): Preparation, optical properties and low power consumption polymeric thermo-optic switch

Azo chromophore molecule (NPMBR) was synthesized by using 4-nitroaniline, sodium nitrite and chiral reagent, R-α-methyl benzylamine. Then, NPMBR was polymerized with isophorone diisocyanate and polyether polyol to obtain novel chiral azo polyurethane(urea) (PUUR). The chemical structures of NPMBR and PUUR were characterized by FTIR and UV-Vis spectroscopy. The UV-induced trans/cis photoisomerization and reflex-isomerization behaviors were investigated and the results indicated that the PUUR solution could undergo photochromism after irradiated by UV light. The measurements of refractive index and thermo-optic coefficient (dn/dT) of PUUR were demonstrated at different wavelengths and different temperatures by ATR technique. By using CCD digital imaging devices, transmission loss of the internal waveguide was measured. The refractive index dispersions and Sellmeyer coefficients of PUUR were obtained by Sellmeyer equation. A Y-branched switch based on thermo-optic effect was proposed and the performance of switch was simulated. With branching angle of 0.143° and FD-BPM method, the result showed that the power consumption of the thermo-optic switch could be only 0.4 mW, and the response time of the switch could reach about 3 ms. It has a significant improvement in reducing the power consumption and response time compared with those of the normal Y-branched polymer thermo-optic switch. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2011

Crosstalk reduced and low power consumption polymeric thermo-optic switch

A new polymeric 1 × 2 thermo-optic switch with significantly low crosstalk and low power consumption is presented. The thermo-optic coefficients of the core layer and the cladding layer are obviously different to each other. The refractive index of the core changes so that it would be less than that of the top cladding when the temperature is sufficiently high. Using this phenomenon, low crosstalk performance is achieved. The result indicated that the crosstalk of the proposed device could be improved from −20 to −60 dB. The switching insertion loss is 1.71 dB and the total heating power is no more than 16 mW.

트렌치 구조를 이용한 저전력 1×2 폴리머 열 광학 스위치의 제작

트렌치 구조를 이용한 저전력 1<TEX>$\times$</TEX>2 폴리머 열 광학 스위치를 제안하고 제작하였다. 최적의 위치에 적절히 형성된 트렌치 구조는 전극으로부터 발생한 열 흐름을 방해하여 전력 소보를 줄이는데 기여할 수 있다 광 도파로를 구성하는 폴리머 층에서의 온도 분포가 변하여 Y-분기를 이루는 두 도파로들 사이의 온도 기울기가 급격하게 증가하기 때문이다. 본 실험에서는 트렌치 구조의 효과를 비교 분석하기 위해 트렌치 구조가 없는 1<TEX>$\times$</TEX>2 폴리머 열 광학 스위치도 동일한 기판 위에 함께 제작하였다. 트렌치 구조를 이용한 열 광학 스위치의 경우, 측정된 누화는 TE 편광에서 -17.0 dB 이하. TM 편광에서 -15.0 dB 이하였다 전력 소모는 트렌치 구조가 없는 열 광학 스위치의 소모 전력보다 25% 감소한 약 66 ㎽였다. A low-power <TEX>$1{\times}2$</TEX> polymeric thermo-optic switch with a trench structure is proposed and fabricated. The trench structure in the optimized region slows down the heat flow from the electrodes, which contributes to the reduction of power consumption. The temperature distribution in the polymer layers has been adjusted to increase the temperature gradient between the two arms of the Y-branch. For comparison, a <TEX>$1{\times}2$</TEX> polymeric thermo-optic switch with no trench structure is fabricated together on the same substrate. In the device with a trench structure, the measured crosstalk is less than -17.0 dB for TE polarization.-15.0 dB for TM polarization. The power consumption is about 66 mW, which is 25% less than that of the device with no trench structure.