OUTLINEd.量子关联分析g.量子计算信息的物理本质a.d.1量子纠缠判断a.1信息和概率g.1量子逻辑门g.2量子算法a.2信息和熔d.2.非定域性和Bel1不等式d.3量子资源a.3经典通信理论量子力学1.0量子信息测度b.e.e.1 vonNeumannb.1QM基本公设(纯态)b.2复合量子系统e.2Trace距离和保真度e.3量子纠缠测度b.3混态和密度矩阵量子力学2.0f.量子测量C.C.1QM基本公设(混态)f.1量子光学器件和探测c.2量子比特f.2广义测量和POVMc.3量子纠缠
OUTLINE a. 信息的物理本质 a.1 信息和概率 a.2 信息和熵 a.3 经典通信理论 b. 量子力学1.0 b.1 QM基本公设(纯态) b.2 复合量子系统 b.3 混态和密度矩阵 c. 量子力学2.0 c.1 QM基本公设(混态) c.2 量子比特 c.3 量子纠缠 d. 量子关联分析 d.1 量子纠缠判断 d.2 非定域性和Bell不等式 d.3 量子资源 e. 量子信息测度 e.1 von Neumann熵 e.2 Trace距离和保真度 e.3 量子纠缠测度 f. 量子测量 f.1 量子光学器件和探测 f.2 广义测量和POVM g. 量子计算 g.1 量子逻辑门 g.2 量子算法
D.量子关联分析d.1量子纠缠判断Theseparabilityproblemoneofthebasicandemergentproblem inpresentandfuturequantuminformationprocessingEnvironment(decoherence)Isaquantumstateentangled?ABHowentangledisitstillafterinteractingwitha noisy environment?
D.量子关联分析 d.1 量子纠缠判断 The separability problem: one of the basic and emergent problem in present and future quantum information processing Is a quantum state entangled? How entangled is it still after interacting with a noisy environment? A B Environment (decoherence)
分离态和纠缠态的物理定义Def :A separable state is a quantumstatewhich canbe prepared ina local or classicalway(Local operationsandclassicalcommunications:LOcC),困难:从无穷多种PA..Z=EpipApB...pZ可能的分解中找到特定的一种Otherwise,itisentangledPA = TrB,C..,z (pAB...z)PB =TrA.C...z (PAB...z)..Pz=TrA,B.Y(pAB...z)各子系统约化密度矩阵LOCC操作"localoperationsandclassicalcommunication"局域操作:unitarydynamicactions,measurements,andallotherlocalmanipulations经典通信:exchangeinformationviaclassicalcommunication
分离态和纠缠态的物理定义 LOCC操作 “local operations and classical communication” 局域操作: unitary dynamic actions, measurements, and all other local manipulations 经典通信: exchange information via classical communication Def:A separable state is a quantum state which can be prepared in a local or classical way (Local operations and classical communications: LOCC), Otherwise, it is entangled. 困难:从无穷多种 可能的分解中找到 特定的一种 各子系统约化密度矩阵
Interlude:LocalOperationsandClassicalCommunication(LocC)Alice和Bob各自持有一个qubit,处于|0)A[0B=00)Alice和Bob各持有一个硬币,若其中一人投出正面(heads),则改变其手中态为[o)一→)若两人都投出正面,则分别改变手中态为|Φ),[x)tails-heads :Job)tails-tails : [00),ClassicalLocal Operation heads-tailsI: [3b0),heads-heads Fsx)Communication(/00)(00|+[0b)(0 + b0)(b0| + [x)(xl)PAB=PROGRAM:K个结果,每个发生概率pk,Alice和Bob对应制备量子态ldk中k),即关于k的信息丢失(pkQkk),k))或者密度算符classical flagK存储程序运行结Zpk lakBx) (akBul[k)(kPABIK果的信息k=1givenk
Interlude:Local Operations and Classical Communication (LOCC) ⚫ Alice 和 Bob 各自持有一个qubit,处于 ⚫ Alice 和 Bob 各持有一个硬币,若其中一人投出正面(heads),则改变其手中态为 若两人都投出正面,则分别改变手中态为 Classical Communication Local Operation PROGRAM:K 个结果,每个发生概率 pk,Alice 和 Bob 对应制备量子态 ȁ𝜓 ۧ 𝑘𝜙𝑘 ,即 或者密度算符 classical flag: 存储程序运行结 果的信息 given k 关于k的信息丢失
Randomnumberk通过LOCC制备(0)AUkKPAB=pk [aβk)<akBe/ < SeparableSeparableVi[0) Bk分离态(Separablestates)(genuine quantuminteraction)10)AU通过global幺正变换制备Entangled[0) BKPABpklakBk)(akBk/Entangledk纠缠态(Entangledstates)
通过 LOCC 制备 通过 global 幺正变换制备 (genuine quantum interaction)