abstract.
... indistinguishable from a real field ±E. In order to precise our questioning, let us first of all consider the gedanken experiment illustrated in Fig.2. A hydrogen atom possesses an electron whose wave function at t=0 is supposed to be a linear combination of 1s and 2p x. The whole atom is placed at ...
... indistinguishable from a real field ±E. In order to precise our questioning, let us first of all consider the gedanken experiment illustrated in Fig.2. A hydrogen atom possesses an electron whose wave function at t=0 is supposed to be a linear combination of 1s and 2p x. The whole atom is placed at ...
Document
... Chemistry 130 (Lecture VII-VIII) Answer 1. Which of the following statements is not consistent with a quantum mechanical view of nature? a. Matter can be thought of as waves b. Excited atoms can emit all possible energies c. Knowing the exact speed of an electron means we do not know anything about ...
... Chemistry 130 (Lecture VII-VIII) Answer 1. Which of the following statements is not consistent with a quantum mechanical view of nature? a. Matter can be thought of as waves b. Excited atoms can emit all possible energies c. Knowing the exact speed of an electron means we do not know anything about ...
Quantum Computing - Department of Physics and Astronomy
... • When the number of transistors goes down, so does the overall dimensions • Transistor size will approach quantum dimensions in ~6-10 years! • We had better be ready to embrace a new approach. ...
... • When the number of transistors goes down, so does the overall dimensions • Transistor size will approach quantum dimensions in ~6-10 years! • We had better be ready to embrace a new approach. ...
Experimental Observation of Impossible-to
... measured the probabilities pði; jÞ and pðj; iÞ with i j. In Fig. 2(f) we report the histogram of the occurrence of different values of probabilities, that quantify the nonorthogonality component of the experimental projectors. We observe a good agreement with the null value expected for orthogonal ...
... measured the probabilities pði; jÞ and pðj; iÞ with i j. In Fig. 2(f) we report the histogram of the occurrence of different values of probabilities, that quantify the nonorthogonality component of the experimental projectors. We observe a good agreement with the null value expected for orthogonal ...
Fibre-based Quantum Key Distribution using phase randomized
... generated in an asymmetric fibre interferometer. The signal pulses are phase modulated and attenuated to weak coherent states. Currently we choose a binary modulation (producing the coherent states |±α〉) and concatenate a series of strong, classical signal pulses as pilot signals. Subsequently, the ...
... generated in an asymmetric fibre interferometer. The signal pulses are phase modulated and attenuated to weak coherent states. Currently we choose a binary modulation (producing the coherent states |±α〉) and concatenate a series of strong, classical signal pulses as pilot signals. Subsequently, the ...
Heralded atomic-ensemble quantum memory for photon polarization states
... through this area many times using mirrors with very low loss [10]. In the optical domain an opacity (or resonant optical depth η) of ∼100 can be achieved in this way [10, 11]. An alternative method for increasing the optical depth is to use an ensemble [1–5], [12], rather than a single particle. It ...
... through this area many times using mirrors with very low loss [10]. In the optical domain an opacity (or resonant optical depth η) of ∼100 can be achieved in this way [10, 11]. An alternative method for increasing the optical depth is to use an ensemble [1–5], [12], rather than a single particle. It ...
Lecture-3: Atomic Structure
... The theory of quantum mechanics was developed by Erwin Schrödinger, Werner. According to quantum mechanics, the position and momentum of a particle cannot both be accurately known at the same time. Only its most probable position or momentum can be determined. The most probable distance between the ...
... The theory of quantum mechanics was developed by Erwin Schrödinger, Werner. According to quantum mechanics, the position and momentum of a particle cannot both be accurately known at the same time. Only its most probable position or momentum can be determined. The most probable distance between the ...
Extrimes of Information Combining
... is the orthogonal projection on is the orthogonal projection on ...
... is the orthogonal projection on is the orthogonal projection on ...
Main Topic: T1 Density-Functional Theory beyond LDA
... Device miniaturization requires an understanding of the dynamical response of materials on the nanometer scale. A great deal of experimental and theoretical work has been devoted to characterizing the excitation, charge, spin, and vibrational dynamics in a variety of novel materials, including carbo ...
... Device miniaturization requires an understanding of the dynamical response of materials on the nanometer scale. A great deal of experimental and theoretical work has been devoted to characterizing the excitation, charge, spin, and vibrational dynamics in a variety of novel materials, including carbo ...
BCK0103-15 Quantum physics (3-0-4) - nuvem
... BCK0103-15 Quantum physics (3-0-4) General goals: The main goal of this course is to present to the student the main concepts of the quantum theory, with the perspective of comprehending the basic phenomena which originate at the atomic scale, their effects and technological applications. ...
... BCK0103-15 Quantum physics (3-0-4) General goals: The main goal of this course is to present to the student the main concepts of the quantum theory, with the perspective of comprehending the basic phenomena which originate at the atomic scale, their effects and technological applications. ...
Quantum Computer
... quantum computer built 2001 - Shor's algorithm executed on 7 qubit computer 2005 - First qubyte created 2009 - Yale creates solidstate quantum processor 2011 - D-Wave announces commercial quantum computer 2011 – Record computation of 3x5=15 ...
... quantum computer built 2001 - Shor's algorithm executed on 7 qubit computer 2005 - First qubyte created 2009 - Yale creates solidstate quantum processor 2011 - D-Wave announces commercial quantum computer 2011 – Record computation of 3x5=15 ...
Einstein-Podolsky-Rosen paradox and Bell`s inequalities
... should be no further interaction. Depending on a measurement of position or momentum on system one, due to the reduction of the wave packet both momentum and position of system two could become an element of reality by their definition. But since the operators for momentum and position do not commut ...
... should be no further interaction. Depending on a measurement of position or momentum on system one, due to the reduction of the wave packet both momentum and position of system two could become an element of reality by their definition. But since the operators for momentum and position do not commut ...
wlq10
... • measurement changes observed system so that parameter measured is subsequently definite • conjugate parameters cannot be simultaneously definite • process measure A, measure B not the same as measure B, measure A ...
... • measurement changes observed system so that parameter measured is subsequently definite • conjugate parameters cannot be simultaneously definite • process measure A, measure B not the same as measure B, measure A ...
Document
... At the Planck scale, Quantum Mechanics is not wrong, but its interpretation may have to be revised, not only for philosophical reasons, but also to enable us to construct more concise theories, recovering e.g. locality (which appears to have been lost in string theory). The “random numbers”, inheren ...
... At the Planck scale, Quantum Mechanics is not wrong, but its interpretation may have to be revised, not only for philosophical reasons, but also to enable us to construct more concise theories, recovering e.g. locality (which appears to have been lost in string theory). The “random numbers”, inheren ...
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.