基于硅基微谐振器的光子模拟和数字信号处理器

发布时间：2018-03-10 20:51

  本文选题：硅光子学　切入点：微型谐振腔　出处：《华中科技大学》2016年博士论文　论文类型：学位论文

【摘要】：虽然在过去的半个多世纪里,高度集成的微电子技术为人们便利的生活、高速的信息互联做出了卓越贡献,但是传统的半导体工业将受限于物理极限而无法继续遵循摩尔定律来进一步发展,并且电子线路中的延迟、功耗和串扰等问题日益突出。硅光集成和互连技术能够将各种光子器件集成到同一芯片上,利用光作为信息载体来进行信号的传输和处理。由于具有超快的处理速率、高集成度和较低的功耗等优势,特别是与成熟的互补金属氧化物半导体(CMOS)工艺相兼容,近十年来硅光芯片集成技术得到了高速发展,已经成为了最具有发展前景的下一代光互连方案。微环等谐振器由于紧凑的尺寸和优异的光学特性一直是硅基光子学的研究热点,已经成为了硅光集成系统中的基本元件。首先,微环腔体的形成不需要腔面,从而能够实现极小尺寸的高度集成；其次,微环中的谐振光可以通过干涉加强而聚积至很高的能量,显著加强了其中的非线性效应,从而对泵浦光能量的要求也较低。特别是硅基微环具有良好的热光效应和等离子色散效应,可以用来对微环的光谱进行操控,基于这些原理已经实现了性能优良的可调光学滤波器、大规模阵列光开关、高速光调制器等多种功能器件。本论文详细介绍了硅基微环的理论基础、设计原则及工艺制作方法,并实际制作了由微环、微盘等构成的多种器件,分别应用于不同的全光信号处理领域,包括模拟微波光子系统和全光数字信号处理等。本论文的研究成果可以概括为以下几个方面：(1)利用双谐振模式的高Q值微盘实现了光生毫米波。利用微盘不同周期的间隔不等的双谐振模式,就可以在光频率梳中选出不同间隔的两个光频率,拍频后就可以得到不同频率的毫米波信号。最终实现了频率277GHz、306GHz和335GHz的毫米波,谐波抑制比大于25dB。(2)利用级联半径不等的双环结构,实现了大调谐范围的微波光子滤波器(MPF)。由于游标卡尺效应,双环的传输谱为间隔成等差数列的周期性双谐振峰。通过调节光载波波长对准不同双谐振峰中心以及在同一双谐振峰中心附近微调,实现了中心频率和3dB带宽分别从2.5GHz～17.5GHz和6GHz～9GHz可调的MPF,且抑制比大于40dB。接着,对滤波方案做了进一步改进,设计并制作了三个并联的电调微环,从而实现了连续可调的MPF。通过加热电极对微环传输谱的连续调控,可以得到“双通道处理器”的滤波光谱,进而实现了中心频率和3dB带宽分别从19GHz-40GHz和5.5GHz-17.5GHz连续可调的MPF。(3)通过优化微盘参数,实际制作出了Q值为1×105的硅基微盘。通过单边带调制和微盘的高Q谐振峰,实现了带宽约为2GHz、抑制比40dB、中心频率从6GHz-18GHz连续可调的MPF。接着,利用所得到的MPF响应实现了10GHz范围的微波频率测量,测量误差±0.1GHz,并且测量范围和测量精度都可以调谐。(4)提出了光纤与硅基芯片联合的机械结构来实现路径非对称光传输。基于光纤和芯片光栅间的热辐射效应,设计了前向光纤固定而后向光纤自由悬浮的结构,实现了带宽大于24nm、非对称传输比高达63dB的光传输。然后还从实验中证明了此器件不仅对连续光工作,而且对高速调制信号同样有效,非对称传输比达到了56dB。(5)在纯硅芯片上基于热光效应实现了全光顺序路由传输,即光信号在芯片中按照特定的顺序在不同端口间依次传输而反向截止。巧妙设计了由Y分支和两个非对称的上下路微环谐振器(上下路的耦合间距不同)构成的光子回路,得到了三端口全光顺序路由传输器件。此器件结构具有可扩展性,每增加一个微环就可以增加一个端口数。为了改善器件工作带宽太窄的缺陷,后续又开发了六端口的传输器件。通过加热电极将各个微环谐振波长与工作波长精确对准,不仅提高了阻隔比,而且也实现了工作范围可调,从一定程度上克服了谐振器用于非对称传输时带宽窄的缺陷。(6)利用硅基芯片实现了全光格雷码编码。首先设别判定比特状态的光功率阈值,通过控制输入微环的谐振光功率来调节微环谱线的红移量,从而可以使微环的传输端和下载端的输出比特状态在“0”和“1”之间切换。控制不同微环相互独立的两个谐振波长的功率分别按照特定的顺序变化,在纯光域内产生了4比特的格雷码。此器件的结构和方案原理具有可扩展性：利用N个微环的N个独立谐振峰就可以实现2N比特的全光格雷码编码。
[Abstract]:Although in the past half century, highly integrated microelectronic technology for convenience of life, has made outstanding contributions to the high-speed interconnection of information, but the traditional semiconductor industry will be limited to the physical limit and can not continue to follow Moore's law to further development, and in the electronic circuit delay, power consumption and crosstalk and other issues have become increasingly prominent. Silicon optical integration and interconnection technology can be integrated into various photonic devices on the same chip, using light as an information carrier for transmission and signal processing. Due to its fast processing speed, high integration and low power consumption and other advantages, especially with the complementary metal oxide semiconductor (CMOS) technology is mature with nearly ten years of silicon chip technology has been rapid development, has become the next generation of optical interconnection scheme. The most promising micro ring resonator by compact The size and excellent optical properties has been a hot research in silicon photonics, has become the basic element of silicon optical integration system. Firstly, the formation of micro ring cavity to cavity surface, which enables the high integration small size; secondly, in the micro ring Xie Zhenguang can strengthen interference and accumulation to a high energy, significantly enhancing the nonlinear effect, which demands on the pump energy is low. Especially the silicon micro ring with thermo optic effect and plasma dispersion effect is good, can be used to control the micro ring spectrum, based on the principle has achieved tunable optical filter with good performance. Large scale optical switch array, high speed optical modulator and other functional devices. This paper introduces the basic theory of silicon based micro ring making method, design principle and process, and the actual production of the micro micro ring. A variety of devices composed of disc, are used in all-optical signal processing in different fields, including the simulation of microwave photonic systems and all-optical digital signal processing. The research results of this thesis can be summarized as follows: (1) the microdisk optical millimeter wave with high Q value. The use of double resonance mode micro disk different periodic intervals ranging from double resonant mode, two optical frequency can be selected at different intervals in the optical frequency comb in the millimeter wave signal frequency can be obtained after different frequency. Finally the frequency of the 277GHz, 306GHz and 335GHz of the millimeter wave, harmonic suppression ratio is greater than 25dB. (2) using the double loop cascade structure radius range, the microwave photonic filter large tuning range (MPF). The effect of vernier caliper, double loop transmission spectrum interval periodic double resonant peak of arithmetic progression. By adjusting the optical carrier wavelength alignment is With the double resonance peaks in the center and near the same double resonance peak center fine-tuning, realize the center frequency and bandwidth of 3dB from 2.5GHz ~ 17.5GHz and 6GHz ~ 9GHz adjustable MPF, and the inhibition ratio is greater than 40dB. then, the filtering scheme has been further developed the design and fabrication of three parallel micro power transfer ring, so as to realize the continuous control of continuous adjustable MPF. by heating the electrode of the micro ring transmission spectrum, can get the "double channel spectral filtering processor", so as to realize the center frequency and bandwidth of 3dB respectively from 19GHz-40GHz and 5.5GHz-17.5GHz continuously adjustable MPF. (3) by optimizing the parameters of the micro disk, the actual produce the Q value is 1 * 105 silicon micro disc. By single sideband modulation and high Q resonant micro disk, the bandwidth is about 2GHz. The inhibition ratio of 40dB, from the 6GHz-18GHz center frequency tunable MPF. then produced by MPF in response to achieve 10 Microwave frequency measurement range of GHz + 0.1GHz, the measurement error, and measurement range and measurement accuracy can be tuned. (4) presents the mechanical structure of combined fiber and silicon chip to realize the path of asymmetric light transmission. The heat radiation effect and optical fiber grating chip on the basis of the design to optical fiber fixing and structure the fiber free floating, the bandwidth is more than 24nm, asymmetric transmission ratio of optical transmission up to 63dB. And then from the experiment proved that this device not only for continuous light work, but also to the high speed modulation signal, asymmetric transmission ratio reached 56dB. (5) in pure silicon chip based on thermo optic effect realization the full order routing, namely the optical signal in the chip in a specific order in different ports in transmission. The reverse cut-off cleverly designed by Y bifurcation and two non symmetrically on the road on the road (micro ring resonator The different coupling spacing) photonic circuit structure, obtained the three port optical transmission devices. The order routing device structure is extensible, every increase of one micro ring can increase a number of ports. In order to improve the device defects bandwidth is too narrow, the subsequent transmission devices and the development of the six ports by heating. Each electrode micro ring resonant wavelength and wavelength precise alignment, not only improves the blocking ratio, but also realize the scope of work can be adjusted in a certain extent overcome the defects when the resonator for asymmetric transmission bandwidth. (6) the use of silicon chip to achieve all-optical gray encoding. First determine optical power equipment the threshold bit state, the resonant optical power by controlling the input micro ring to adjust the micro ring redshift of the spectrum, which can make the output bit micro ring transmission terminal and the download end in "0" and "1" Switch between different power control micro ring resonant wavelength of two independent respectively in accordance with the order of specific changes, resulting in 4 bit gray code in pure optical domain. The principle structure and scheme of this device is scalable: All-optical gray encoding with N N independent micro ring resonant peak can be the 2N bit.

【学位授予单位】：华中科技大学
【学位级别】：博士
【学位授予年份】：2016
【分类号】：TN911.7
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本文编号：1595029