Electronic Structure of Multi-Electron Quantum Dots
... an axis, the result is either + ÅÅÅÅ2—Å or - ÅÅÅÅ—2Å . Conventionally, we denote this axis as the z-axis and work in units in which — is one. The two spin eigenstates in which we are certain of the electron’s spin projection are denoted a and b, which are the ...
... an axis, the result is either + ÅÅÅÅ2—Å or - ÅÅÅÅ—2Å . Conventionally, we denote this axis as the z-axis and work in units in which — is one. The two spin eigenstates in which we are certain of the electron’s spin projection are denoted a and b, which are the ...
Sourcing semiclassical gravity from spontaneously localized
... where δϱt ðrÞ is a white-noise in time with a potentially nontrivial space correlator which we will specify later. In CSL or DP, the same quantity ϱt ðrÞ is formally a fundamental stochastic (classical) field of the theory which can be taken as physical.2 In the following section, we will use this f ...
... where δϱt ðrÞ is a white-noise in time with a potentially nontrivial space correlator which we will specify later. In CSL or DP, the same quantity ϱt ðrÞ is formally a fundamental stochastic (classical) field of the theory which can be taken as physical.2 In the following section, we will use this f ...
A blueprint for building a quantum computer
... these technologies result in qubit devices that are macroscopic, or nearly so, with areal densities a million times less than computer chips. This fact will have enormous impact on largescale architectures, as we will see. First steps in quantum architecture. At this lowest level, the job of quantum ...
... these technologies result in qubit devices that are macroscopic, or nearly so, with areal densities a million times less than computer chips. This fact will have enormous impact on largescale architectures, as we will see. First steps in quantum architecture. At this lowest level, the job of quantum ...
Non-local quantum effects in cosmology 1
... equations governing the scale factor a(t), which in the classical theory are local differential equations. The effects of loops will generate new contributions where the equation for the scale factor depends on what the scale factor was doing in the past. We refer to this effect as the quantum memor ...
... equations governing the scale factor a(t), which in the classical theory are local differential equations. The effects of loops will generate new contributions where the equation for the scale factor depends on what the scale factor was doing in the past. We refer to this effect as the quantum memor ...
Operator Quantum Error Correction.
... Thus, Eqs. (11,12) are satisfied and it follows from Theorem 1 that B1 is a noiseless subsystem (a subspace in this case) for E. To see this explicitly, let σ ∈ B(HB1 ) be arbitrary, and so σ = a|01ih01| + b|01ih10| + c|10ih01| + d|10ih10|, for some a, b, c, d ∈ C. Then E(σ) = E0 σE0† + E1 σE1† = σ, ...
... Thus, Eqs. (11,12) are satisfied and it follows from Theorem 1 that B1 is a noiseless subsystem (a subspace in this case) for E. To see this explicitly, let σ ∈ B(HB1 ) be arbitrary, and so σ = a|01ih01| + b|01ih10| + c|10ih01| + d|10ih10|, for some a, b, c, d ∈ C. Then E(σ) = E0 σE0† + E1 σE1† = σ, ...
Program and Booklet - Fakultät für Mathematik
... We present an in-depth analysis regarding the error resistance and optimization of our all-optical Bell measurement and ultrafast long-distance quantum communication scheme proposed in [arXiv:1503.06777]. In order to promote our previous proposal from loss- to fault-tolerance, we introduce a general ...
... We present an in-depth analysis regarding the error resistance and optimization of our all-optical Bell measurement and ultrafast long-distance quantum communication scheme proposed in [arXiv:1503.06777]. In order to promote our previous proposal from loss- to fault-tolerance, we introduce a general ...
Towards a Quantum Field Theory of Mind
... either in memory or what was being looked at. But in quantum physics we’ve learned that when you’re looking at very small objects, subatomic particles for example, the very action of looking at them disturbs them to such an extent that we never really get a complete picture as to what they actually ...
... either in memory or what was being looked at. But in quantum physics we’ve learned that when you’re looking at very small objects, subatomic particles for example, the very action of looking at them disturbs them to such an extent that we never really get a complete picture as to what they actually ...
PDF only - at www.arxiv.org.
... speaking, both heads and tails are possibilities. In an actual toss, however, only heads or tails will show up. We shall refer to this view of the objects of the everyday world as the classically-definite (CDEF) conception of an object and its state. According to this CDEF conception, an object is a ...
... speaking, both heads and tails are possibilities. In an actual toss, however, only heads or tails will show up. We shall refer to this view of the objects of the everyday world as the classically-definite (CDEF) conception of an object and its state. According to this CDEF conception, an object is a ...
Quantum key distribution
Quantum key distribution (QKD) uses quantum mechanics to guarantee secure communication. It enables two parties to produce a shared random secret key known only to them, which can then be used to encrypt and decrypt messages. It is often incorrectly called quantum cryptography, as it is the most well known example of the group of quantum cryptographic tasks.An important and unique property of quantum key distribution is the ability of the two communicating users to detect the presence of any third party trying to gain knowledge of the key. This results from a fundamental aspect of quantum mechanics: the process of measuring a quantum system in general disturbs the system. A third party trying to eavesdrop on the key must in some way measure it, thus introducing detectable anomalies. By using quantum superpositions or quantum entanglement and transmitting information in quantum states, a communication system can be implemented which detects eavesdropping. If the level of eavesdropping is below a certain threshold, a key can be produced that is guaranteed to be secure (i.e. the eavesdropper has no information about it), otherwise no secure key is possible and communication is aborted.The security of encryption that uses quantum key distribution relies on the foundations of quantum mechanics, in contrast to traditional public key cryptography which relies on the computational difficulty of certain mathematical functions, and cannot provide any indication of eavesdropping at any point in the communication process, or any mathematical proof as to the actual complexity of reversing the one-way functions used. QKD has provable security based on information theory, and forward secrecy.Quantum key distribution is only used to produce and distribute a key, not to transmit any message data. This key can then be used with any chosen encryption algorithm to encrypt (and decrypt) a message, which can then be transmitted over a standard communication channel. The algorithm most commonly associated with QKD is the one-time pad, as it is provably secure when used with a secret, random key. In real world situations, it is often also used with encryption using symmetric key algorithms like the Advanced Encryption Standard algorithm. In the case of QKD this comparison is based on the assumption of perfect single-photon sources and detectors, that cannot be easily implemented.