Eavesdropping of two-way coherent-state quantum cryptography via gaussian quantum cloning machines
... conjugate observables. This is accomplished by a heterodyne detection [8] of the state, which will give an outcome ζ ≈ α + β. After the subtraction of the known value Bob achieves an estimate α of Alice’s complex amplitude α, i.e., xA ≈ xA and pA ≈ pA . In the case of a noiseless channel between ...
... conjugate observables. This is accomplished by a heterodyne detection [8] of the state, which will give an outcome ζ ≈ α + β. After the subtraction of the known value Bob achieves an estimate α of Alice’s complex amplitude α, i.e., xA ≈ xA and pA ≈ pA . In the case of a noiseless channel between ...
Quantum state majorization at the output of bosonic Gaussian
... [7, 8], which obviously does not change the entropy. Since coherent states are equivalent up to displacement operations it means that K coincides with the whole set of coherent states. Majorization at the output of the channel. We can finally state our main result which proves the validity of the ma ...
... [7, 8], which obviously does not change the entropy. Since coherent states are equivalent up to displacement operations it means that K coincides with the whole set of coherent states. Majorization at the output of the channel. We can finally state our main result which proves the validity of the ma ...
An Extreme form of Superactivation for Quantum Zero-Error
... information to include quantum messages leads to new insights and applications, such as quantum cryptography and quantum computing. Because quantum systems are notoriously delicate, error correction is extremely important, and the capacities of a noisy quantum channel for transmitting various types ...
... information to include quantum messages leads to new insights and applications, such as quantum cryptography and quantum computing. Because quantum systems are notoriously delicate, error correction is extremely important, and the capacities of a noisy quantum channel for transmitting various types ...
On the role of entanglement in quantum information
... attempt to gain some knowledge about it. Actually, a measurement performed on the quantum system in which the key is encoded in general perturbs it and the perturbation can be detected by the legitimate users. The security of the key distribution process is then guaranteed by the laws of quantum mec ...
... attempt to gain some knowledge about it. Actually, a measurement performed on the quantum system in which the key is encoded in general perturbs it and the perturbation can be detected by the legitimate users. The security of the key distribution process is then guaranteed by the laws of quantum mec ...
Fixed points of quantum operations
... For this case we shall show that B(H)φA = A . Thus, a noisy quantum channel does not disturb a state ρ if and only if ρ is compatible with the operation elements Ai , i = 1, 2, . . . . Related results and methods may be found in [1]. 2. Completely Positive Maps This section studies completely posit ...
... For this case we shall show that B(H)φA = A . Thus, a noisy quantum channel does not disturb a state ρ if and only if ρ is compatible with the operation elements Ai , i = 1, 2, . . . . Related results and methods may be found in [1]. 2. Completely Positive Maps This section studies completely posit ...
Photonic Communications and Quantum Information Storage
... results are plotted for both the quantized and quantum channel capacities, spectral efficiencies and the information storage capacities. The results demonstrate the feasibility of Terabit per sec to Petabit per sec data rates and Petabyte information storage capacities of 2/ln2 bits/ photon or one q ...
... results are plotted for both the quantized and quantum channel capacities, spectral efficiencies and the information storage capacities. The results demonstrate the feasibility of Terabit per sec to Petabit per sec data rates and Petabyte information storage capacities of 2/ln2 bits/ photon or one q ...
Classical World because of Quantum Physics
... I.e. the statistical mixture has a classical time evolution, if measurement and time evolution commute “on the coarse-grained level”. Given fuzzy measurements (or pre-measurement decoherence), it depends on the Hamiltonian whether macrorealism is satisfied. ...
... I.e. the statistical mixture has a classical time evolution, if measurement and time evolution commute “on the coarse-grained level”. Given fuzzy measurements (or pre-measurement decoherence), it depends on the Hamiltonian whether macrorealism is satisfied. ...
pptx
... SDPs in quantum information 1. Goal: approximate Sep Relaxation: k-extendable + PPT 2. Goal: λmin for Hamiltonian on n qudits Relaxation: L : k-local observables R such that L[X†X] ≥ 0 for all k/2-local X. 3. Goal: entangled value of multiplayer games Relaxation: L : products of ≤k operators R ...
... SDPs in quantum information 1. Goal: approximate Sep Relaxation: k-extendable + PPT 2. Goal: λmin for Hamiltonian on n qudits Relaxation: L : k-local observables R such that L[X†X] ≥ 0 for all k/2-local X. 3. Goal: entangled value of multiplayer games Relaxation: L : products of ≤k operators R ...