本文選題：符合測(cè)量 + 單光子探測(cè)器��； 參考：《聊城大學(xué)》2017年碩士論文

【摘要】：符合測(cè)量借助電子學(xué)的手段將時(shí)間相關(guān)的脈沖從不同探測(cè)器的輸出脈沖中選擇出來。攜帶量子信息的單光子可以通過單光子探測(cè)器檢測(cè),并將此轉(zhuǎn)換為電信號(hào),進(jìn)而輸出,最后通過符合測(cè)量和符合計(jì)數(shù)等措施來獲得單光子所攜帶的信息。單光子符合探測(cè)在單光子源的研究、量子操作、多光子干涉、糾纏光子對(duì)的判定、單光子干涉的研究、全光量子計(jì)算等量子通信與信息領(lǐng)域有著極其重要的應(yīng)用。對(duì)于符合計(jì)數(shù),它可以用乘法器與門等分立元件來實(shí)現(xiàn),但是分立元件會(huì)給信號(hào)帶來額外的延遲。近幾年,由于基于現(xiàn)場(chǎng)可編程門陣列(FPGA)的迅速發(fā)展,FPGA具有更多的門電路,體積更小,成本更低,并且方便隨時(shí)修改設(shè)計(jì)直至滿足實(shí)驗(yàn)要求。越來越多的人選擇使用FPGA設(shè)計(jì)符合計(jì)數(shù)系統(tǒng),但是許多系統(tǒng)的設(shè)計(jì)存在同一個(gè)問題:兩通道信號(hào)到達(dá)FPGA引入的路徑延遲不一致性而帶來符合計(jì)數(shù)誤差。為了解決這一問題,針對(duì)外部觸發(fā)的單光子探測(cè)器,我們實(shí)驗(yàn)室對(duì)脈沖邊沿觸發(fā)型的單光子探測(cè)器進(jìn)行符合計(jì)數(shù)器的設(shè)計(jì),并且驗(yàn)證了合理性。主要內(nèi)容有以下兩個(gè)部分:第一:論述了符合測(cè)量的基本原理、方法和多種單光子探測(cè)器,比較了幾種單光子探測(cè)器的使用范圍。針對(duì)外部觸發(fā)的單光子探測(cè)器,設(shè)計(jì)了雙通道符合計(jì)數(shù)系統(tǒng)。整個(gè)符合系統(tǒng)的設(shè)計(jì)分為了“聯(lián)合整形”,延遲符合和符合計(jì)數(shù)三個(gè)部分。其中,難點(diǎn)在于“聯(lián)合整形”的處理,這也是本論文的創(chuàng)新之處。它成功解決了由路徑延遲而引起的誤差。我們通過QuartusⅡ調(diào)用ModelSim-Altera進(jìn)行仿真,驗(yàn)證了系統(tǒng)的正確性。第二:介紹了單光子源的二階相關(guān)函數(shù)。在實(shí)驗(yàn)中首次采用了基于摻鉺光纖的單光子源,二階相關(guān)函數(shù)是評(píng)價(jià)單光子源的最重要的指標(biāo)。我們通過符合測(cè)量來測(cè)得二階相關(guān)函數(shù),以此來評(píng)價(jià)基于摻鉺光纖的單光子源。本論文所設(shè)計(jì)的符合計(jì)數(shù)系統(tǒng)和以往的符合計(jì)數(shù)系統(tǒng)相比具有更好的精確性,能夠更加準(zhǔn)確地完成單光子探測(cè)相關(guān)的實(shí)驗(yàn)。
[Abstract]:Coincidence measurement selects time-dependent pulses from the output pulses of different detectors by electronic means. A single photon carrying quantum information can be detected by a single photon detector and converted into an electrical signal and then output. Finally, the information carried by a single photon can be obtained by means of coincidence measurement and coincidence counting. Single-photon coincidence detection has important applications in the field of quantum communication and information, such as the study of single photon source, quantum operation, multi-photon interference, determination of entangled photon pair, single-photon interference and all-optical quantum computation. For coincidence counting, it can be implemented by discrete elements such as multipliers and gates, but the discrete elements can cause additional delay to the signal. In recent years, due to the rapid development of FPGA based on Field Programmable Gate Array (FPGA), FPGA has more gate circuits, smaller size, lower cost, and is convenient to modify the design at any time to meet the experimental requirements. More and more people choose to use FPGA to design the coincidence counting system, but many systems have the same problem: the inconsistency of path delay introduced by the two-channel signal arrival FPGA leads to the coincidence counting error. In order to solve this problem, we designed a coincidence counter for the externally triggered single-photon detector in our laboratory, and verified the rationality. The main contents are as follows: first, the basic principle and method of coincidence measurement and several kinds of single-photon detectors are discussed, and the application range of several single-photon detectors is compared. A double channel coincidence counting system is designed for the external triggered single photon detector. The design of the whole coincidence system is divided into three parts: joint shaping, delay coincidence and coincidence counting. Among them, the difficulty lies in the treatment of joint plastic surgery, which is also the innovation of this paper. It successfully solves the error caused by path delay. The correctness of the system is verified by Quartus 鈪，

本文編號(hào)：1953370