- 1 Introduction and overview
- 1.1 Global perspectives
- 1.2 Quantum bits
- 1.3 Quantum computation
- 1.3.1 Single qubit gates
- [1.3.2 Multiple qubit gates]
- [1.3.3 Measurements in bases other than the computational basis]
- [1.3.4 Quantum circuits]
- [1.3.5 Qubit copying circuit?]
- [1.3.6 Example: Bell states]
- [1.3.7 Example: quantum teleportation]
- [1.4 Quantum algorithms]
- [1.4.1 Classical computations on a quantum computer]
- [1.4.2 Quantum parallelism]
- [1.4.3 Deutsch’s algorithm]
- [1.4.4 The Deutsch–Jozsa algorithm]
- [1.4.5 Quantum algorithms summarized]
- [1.5 Experimental quantum information processing]
- [1.5.1 The Stern–Gerlach experiment]
- [1.5.2 Prospects for practical quantum information processing]
- [1.6 Quantum information]
- [1.6.1 Quantum information theory: example problems]
- [1.6.2 Quantum information in a wider context]
- [2 Introduction to quantum mechanics]
- [2.1 Linear algebra]
- [2.1.1 Bases and linear independence]
- [2.1.2 Linear operators and matrices]
- [2.1.3 The Pauli matrices]
- [2.1.4 Inner products]
- [2.1.5 Eigenvectors and eigenvalues]
- [2.1.6 Adjoints and Hermitian operators]
- [2.1.7 Tensor products]
- [2.1.8 Operator functions]
- [2.1.9 The commutator and anti-commutator]
- [2.1.10 The polar and singular value decompositions]
- [2.2 The postulates of quantum mechanics]
- [2.2.1 State space]
- [2.2.2 Evolution]
- [2.2.3 Quantum measurement]
- [2.2.4 Distinguishing quantum states]
- [2.2.5 Projective measurements]
- [2.2.6 POVM measurements]
- [2.2.7 Phase]
- [2.2.8 Composite systems]
- [2.2.9 Quantum mechanics: a global view]
- [2.3 Application: superdense coding]
- [2.4 The density operator]
- [2.4.1 Ensembles of quantum states]
- [2.4.2 General properties of the density operator]
- [2.4.3 The reduced density operator]
- [2.5 The Schmidt decomposition and purifications]
- [2.6 EPR and the Bell inequality]
- [2.1 Linear algebra]
- [3 Introduction to computer science]
- [3.1 Models for computation]
- [3.1.1 Turing machines]
- [3.1.2 Circuits]
- [3.2 The analysis of computational problems]
- [3.2.1 How to quantify computational resources]
- [3.2.2 Computational complexity]
- [3.2.3 Decision problems and the complexity classes P and NP]
- [3.2.4 A plethora of complexity classes]
- [3.2.5 Energy and computation]
- [3.3 Perspectives on computer science]
- [3.1 Models for computation]
- [4 Quantum circuits]
- [4.1 Quantum algorithms]
- [4.2 Single qubit operations]
- [4.3 Controlled operations]
- [4.4 Measurement]
- [4.5 Universal quantum gates]
- [4.5.1 Two-level unitary gates are universal]
- [4.5.2 Single qubit and CNOT gates are universal]
- [4.5.3 A discrete set of universal operations]
- [4.5.4 Approximating arbitrary unitary gates is generically hard]
- [4.5.5 Quantum computational complexity]
- [4.6 Summary of the quantum circuit model of computation]
- [4.7 Simulation of quantum systems]
- [4.7.1 Simulation in action]
- [4.7.2 The quantum simulation algorithm]
- [4.7.3 An illustrative example]
- [4.7.4 Perspectives on quantum simulation]
- [5 The quantum Fourier transform and its applications]
- [5.1 The quantum Fourier transform]
- [5.2 Phase estimation]
- [5.2.1 Performance and requirements]
- [5.3 Applications: order-finding and factoring]
- [5.3.1 Application: order-finding]
- [5.3.2 Application: factoring]
- [5.4 General applications of the quantum Fourier transform]
- [5.4.1 Period-finding]
- [5.4.2 Discrete logarithms]
- [5.4.3 The hidden subgroup problem]
- [5.4.4 Other quantum algorithms?]
- [6 Quantum search algorithms]
- [6.1 The quantum search algorithm]
- [6.1.1 The oracle]
- [6.1.2 The procedure]
- [6.1.3 Geometric visualization]
- [6.1.4 Performance]
- [6.2 Quantum search as a quantum simulation]
- [6.3 Quantum counting]
- [6.4 Speeding up the solution of NP-complete problems]
- [6.5 Quantum search of an unstructured database]
- [6.6 Optimality of the search algorithm]
- [6.7 Black box algorithm limits]
- [6.1 The quantum search algorithm]
- [7 Quantum computers: physical realization]
- [7.1 Guiding principles]
- [7.2 Conditions for quantum computation]
- [7.2.1 Representation of quantum information]
- [7.2.2 Performance of unitary transformations]
- [7.2.3 Preparation of fiducial initial states]
- [7.2.4 Measurement of output result 282]
- [7.3 Harmonic oscillator quantum computer]
- [7.3.1 Physical apparatus]
- [7.3.2 The Hamiltonian]
- [7.3.3 Quantum computation]
- [7.3.4 Drawbacks]
- [7.4 Optical photon quantum computer]
- [7.4.1 Physical apparatus]
- [7.4.2 Quantum computation]
- [7.4.3 Drawbacks]
- 7.5 Optical cavity quantum electrodynamics]
- [7.5.1 Physical apparatus]
- [7.5.2 The Hamiltonian]
- [7.5.3 Single-photon single-atom absorption and refraction]
- [7.5.4 Quantum computation]
- [7.6 Ion traps]
- [7.6.1 Physical apparatus]
- [7.6.2 The Hamiltonian]
- [7.6.3 Quantum computation]
- [7.6.4 Experiment]
- [7.7 Nuclear magnetic resonance]
- [7.7.1 Physical apparatus]
- [7.7.2 The Hamiltonian]
- [7.7.3 Quantum computation]
- [7.7.4 Experiment]
- [7.8 Other implementation schemes]
- [8 Quantum noise and quantum operations]
- [8.1 Classical noise and Markov processes]
- [8.2 Quantum operations]
- [8.2.1 Overview]
- [8.2.2 Environments and quantum operations]
- [8.2.3 Operator-sum representation]
- [8.2.4 Axiomatic approach to quantum operations]
- [8.3 Examples of quantum noise and quantum operations]
- [8.3.1 Trace and partial trace]
- [8.3.2 Geometric picture of single qubit quantum operations]
- [8.3.3 Bit flip and phase flip channels]
- [8.3.4 Depolarizing channel]
- [8.3.5 Amplitude damping]
- [8.3.6 Phase damping]
- [8.4 Applications of quantum operations]
- [8.4.1 Master equations]
- [8.4.2 Quantum process tomography]
- [8.5 Limitations of the quantum operations formalism]
- [9 Distance measures for quantum information]
- [9.1 Distance measures for classical information]
- [9.2 How close are two quantum states?]
- [9.2.1 Trace distance]
- [9.2.2 Fidelity]
- [9.2.3 Relationships between distance measures]
- [9.3 How well does a quantum channel preserve information?]
- [10 Quantum error-correction]
- [10.1 Introduction]
- [10.1.1 The three qubit bit flip code]
- [10.1.2 Three qubit phase flip code]
- [10.2 The Shor code]
- [10.3 Theory of quantum error-correction]
- [10.3.1 Discretization of the errors]
- [10.3.2 Independent error models]
- [10.3.3 Degenerate codes]
- [10.3.4 The quantum Hamming bound]
- [10.4 Constructing quantum codes]
- [10.4.1 Classical linear codes]
- [10.4.2 Calderbank–Shor–Steane codes]
- [10.5 Stabilizer codes]
- [10.5.1 The stabilizer formalism]
- [10.5.2 Unitary gates and the stabilizer formalism]
- [10.5.3 Measurement in the stabilizer formalism]
- [10.5.4 The Gottesman–Knill theorem]
- [10.5.5 Stabilizer code constructions]
- [10.5.6 Examples]
- [10.5.7 Standard form for a stabilizer code]
- [10.5.8 Quantum circuits for encoding, decoding, and correction]
- [10.6 Fault-tolerant quantum computation]
- [10.6.1 Fault-tolerance: the big picture]
- [10.6.2 Fault-tolerant quantum logic]
- [10.6.3 Fault-tolerant measurement]
- [10.6.4 Elements of resilient quantum computation]
- [10.1 Introduction]
- [11 Entropy and information]
- [11.1 Shannon entropy]
- [11.2 Basic properties of entropy]
- [11.2.1 The binary entropy]
- [11.2.2 The relative entropy]
- [11.2.3 Conditional entropy and mutual information]
- [11.2.4 The data processing inequality]
- [11.3 Von Neumann entropy]
- [11.3.1 Quantum relative entropy]
- [11.3.2 Basic properties of entropy]
- [11.3.3 Measurements and entropy]
- [11.3.4 Subadditivity]
- [11.3.5 Concavity of the entropy]
- [11.3.6 The entropy of a mixture of quantum states]
- [11.4 Strong subadditivity]
- [11.4.1 Proof of strong subadditivity]
- [11.4.2 Strong subadditivity: elementary applications]
- [12 Quantum information theory]
- [12.1 Distinguishing quantum states and the accessible information]
- [12.1.1 The Holevo bound]
- [12.1.2 Example applications of the Holevo bound]
- [12.2 Data compression]
- [12.2.1 Shannon’s noiseless channel coding theorem]
- [12.2.2 Schumacher’s quantum noiseless channel coding theorem]
- [12.3 Classical information over noisy quantum channels]
- [12.3.1 Communication over noisy classical channels]
- [12.3.2 Communication over noisy quantum channels]
- [12.4 Quantum information over noisy quantum channels]
- [12.4.1 Entropy exchange and the quantum Fano inequality]
- [12.4.2 The quantum data processing inequality]
- [12.4.3 Quantum Singleton bound]
- [12.4.4 Quantum error-correction, refrigeration and Maxwell’s demon]
- [12.5 Entanglement as a physical resource]
- [12.5.1 Transforming bi-partite pure state entanglement]
- [12.5.2 Entanglement distillation and dilution]
- [12.5.3 Entanglement distillation and quantum error-correction]
- [12.6 Quantum cryptography]
- [12.6.1 Private key cryptography]
- [12.6.2 Privacy amplification and information reconciliation]
- [12.6.3 Quantum key distribution]
- [12.6.4 Privacy and coherent information]
- [12.6.5 The security of quantum key distribution]
- [12.1 Distinguishing quantum states and the accessible information]
- [Appendix 1: Notes on basic probability theory]
- [Appendix 2: Group theory]
- [A2.1 Basic definitions]
- [A2.1.1 Generators]
- [A2.1.2 Cyclic groups]
- [A2.1.3 Cosets]
- [A2.2 Representations]
- [A2.2.1 Equivalence and reducibility]
- [A2.2.2 Orthogonality]
- [A2.2.3 The regular representation]
- [A2.3 Fourier transforms]
- [A2.1 Basic definitions]
- [Appendix 3: The Solovay--Kitaev theorem]
- [Appendix 4: Number theory]
- [A4.1 Fundamentals]
- [A4.2 Modular arithmetic and Euclid’s algorithm]
- [A4.3 Reduction of factoring to order-finding]
- [A4.4 Continued fractions]
- [Appendix 5: Public key cryptography and the RSA cryptosystem]
- [Appendix 6: Proof of Lieb’s theorem]