StMalloQuantumComputing
... Quantum Latin word meaning “some quantity”. In physics used with the same meaning as the word discrete in mathematics, i.e., some quantity or variable that can take only sharply defined values as opposed to a continuously varying quantity. The concepts continuum and continuous are known from geome ...
... Quantum Latin word meaning “some quantity”. In physics used with the same meaning as the word discrete in mathematics, i.e., some quantity or variable that can take only sharply defined values as opposed to a continuously varying quantity. The concepts continuum and continuous are known from geome ...
Spin and orbital Kondo effect in electrostatically coupled quantum dots S. L
... transparency region (VSD, h ≈ 0) corresponds to the spin Kondo effect at the dots (εi+ = εi–, 2*SU(2)). The enhanced conductance in this region, marked by the dark circle, is due to the orbital Kondo effect (ε1+ = ε2– for g1 = g2, or ε1+ = ε2+ for g1 = –g2). The orbital degeneracy for the same spin ...
... transparency region (VSD, h ≈ 0) corresponds to the spin Kondo effect at the dots (εi+ = εi–, 2*SU(2)). The enhanced conductance in this region, marked by the dark circle, is due to the orbital Kondo effect (ε1+ = ε2– for g1 = g2, or ε1+ = ε2+ for g1 = –g2). The orbital degeneracy for the same spin ...
A tutorial on Quantum Cohomology
... – Let M be the space of connections on a vector bundle over a compact 3-dimensional manifold X and f = CS be the Chern-Simons functional. Then (1) is the Yang-Mills equation on the 4-manifold X × R, and (2) is the (anti-)selfduality equation. Solutions of the anti-selfduality equation (called instan ...
... – Let M be the space of connections on a vector bundle over a compact 3-dimensional manifold X and f = CS be the Chern-Simons functional. Then (1) is the Yang-Mills equation on the 4-manifold X × R, and (2) is the (anti-)selfduality equation. Solutions of the anti-selfduality equation (called instan ...
Quantum Spin Hall Effect and their Topological Design of Devices
... 2 Dimensional semiconductors are designed on the basis of three classes of the topological insulators and the manager of the charge conservation symmetry and spin- S z conservation symmetry, which establish certain behavior of the manager scopes to the time reversal symmetry, relating the periodic ...
... 2 Dimensional semiconductors are designed on the basis of three classes of the topological insulators and the manager of the charge conservation symmetry and spin- S z conservation symmetry, which establish certain behavior of the manager scopes to the time reversal symmetry, relating the periodic ...
Quantum 2 Info - Ms. Gamm
... back down, and emit visible light photons, but they do so at a great many wavelengths, very nearly a complete spectrum. This is the light that you see. Remember the absorption spectrum with the Fraunhofer lines? It turned out that the wavelengths absorbed by the atoms represent the photons that have ...
... back down, and emit visible light photons, but they do so at a great many wavelengths, very nearly a complete spectrum. This is the light that you see. Remember the absorption spectrum with the Fraunhofer lines? It turned out that the wavelengths absorbed by the atoms represent the photons that have ...
Quantum algorithms for shortest paths problems in structured instances
... Grover search. To obtain the best running time, one can set ℓ so that n2.5 / ℓ = ℓn2.5−ε , and the exponent of the runtime is always < 2.5. We go one step further to improve the obtained runtimes by noticing that one does not need to do an extra Grover search to compute mins∈S d(u, s) + d(s, v). One ...
... Grover search. To obtain the best running time, one can set ℓ so that n2.5 / ℓ = ℓn2.5−ε , and the exponent of the runtime is always < 2.5. We go one step further to improve the obtained runtimes by noticing that one does not need to do an extra Grover search to compute mins∈S d(u, s) + d(s, v). One ...
Density matrices
... is that it provides a convenient tool with which to describe projectors, and thus quantum measurements. Recall: The projector P onto sp e1 , e2 acts as P e1 e2 e3 e1 e2 This gives us a simple explicit formula for P , since e1 e1 e2 e2 e1 e2 e3 e1 e ...
... is that it provides a convenient tool with which to describe projectors, and thus quantum measurements. Recall: The projector P onto sp e1 , e2 acts as P e1 e2 e3 e1 e2 This gives us a simple explicit formula for P , since e1 e1 e2 e2 e1 e2 e3 e1 e ...
No Slide Title
... For such systems L is a constant of motion, e.g. does not change with time since dL dt = 0 In quantum mechanics an operator O representing a constant of motion will commute with the Hamiltonian which means that we can find eigenfunctions that are both eigenfunctions to H and O ...
... For such systems L is a constant of motion, e.g. does not change with time since dL dt = 0 In quantum mechanics an operator O representing a constant of motion will commute with the Hamiltonian which means that we can find eigenfunctions that are both eigenfunctions to H and O ...
II: Experimental Atomic Spectroscopy
... degeneracy. An additional quantum number ms is needed to describe the electron spin. For the alkali “one-electron” atoms the spin-orbit coupling produces an appreciable splitting of all but the = 0 lines with a separation which increases with Z but for a given atom decreases with increasing n. The ...
... degeneracy. An additional quantum number ms is needed to describe the electron spin. For the alkali “one-electron” atoms the spin-orbit coupling produces an appreciable splitting of all but the = 0 lines with a separation which increases with Z but for a given atom decreases with increasing n. The ...
- Free Documents
... functional outcome of divination practices. Anecdotal reports are more common but have only limited scientific value. In some instances such reports can be persuasive. Let us review now three cases from widely separated locations worldwide. A Tungus shaman in Siberia agrees to the request of tribal ...
... functional outcome of divination practices. Anecdotal reports are more common but have only limited scientific value. In some instances such reports can be persuasive. Let us review now three cases from widely separated locations worldwide. A Tungus shaman in Siberia agrees to the request of tribal ...
Weak antilocalization and spin relaxation in integrable quantum dots O Z
... from the constructive interference of backscattered waves, reducing the conductance for systems with time-reversal symmetry, SO coupling turns constructive interference into destructive interference and hence causes an enhanced conductance, i.e. AL. Recently, weak AL has been reconsidered in a numbe ...
... from the constructive interference of backscattered waves, reducing the conductance for systems with time-reversal symmetry, SO coupling turns constructive interference into destructive interference and hence causes an enhanced conductance, i.e. AL. Recently, weak AL has been reconsidered in a numbe ...
Neural Unpredictability, The Interpretation of Quantum Theory, and
... based, then our foundations are built on sand. Wallace (2001b) has argued that this is not important. According to him, worlds in a many-worlds theory or minds in a manyminds theory are like tigers and a tiger is “any pattern which behaves as a tiger”. The problem with this is that although “behavio ...
... based, then our foundations are built on sand. Wallace (2001b) has argued that this is not important. According to him, worlds in a many-worlds theory or minds in a manyminds theory are like tigers and a tiger is “any pattern which behaves as a tiger”. The problem with this is that although “behavio ...
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.