Algorithms and Architectures for Quantum Computers—I. Chuang
... computer over the next few decades. Based on our successes with realizing small quantum computers, and after three years of testing, modeling, and planning, we have come to understand how this can be achieved by combining fault tolerance techniques developed by von Neumann, with methods from atomic ...
... computer over the next few decades. Based on our successes with realizing small quantum computers, and after three years of testing, modeling, and planning, we have come to understand how this can be achieved by combining fault tolerance techniques developed by von Neumann, with methods from atomic ...
poster
... MATTER DIFFRACTION: A time-lapse film compiled from experimental data visually demonstrates for students… A …the detection of individual electrons as particles… B …that collectively form a fringe pattern over time. [REF. 3] ...
... MATTER DIFFRACTION: A time-lapse film compiled from experimental data visually demonstrates for students… A …the detection of individual electrons as particles… B …that collectively form a fringe pattern over time. [REF. 3] ...
14 - University of Utah Physics
... We have omitted one last tricky detail, but we will come back to that. First, stop and think a bit more about what is happening in the erasing process we just described, because that is where the weirdness lies. When we detect the position where one of the photons scattered, we learn which slit its ...
... We have omitted one last tricky detail, but we will come back to that. First, stop and think a bit more about what is happening in the erasing process we just described, because that is where the weirdness lies. When we detect the position where one of the photons scattered, we learn which slit its ...
Word Format
... These rules can be used to extrapolate QM results to classical physics, but were usually used to determine QM selection rules from classical physics. ...
... These rules can be used to extrapolate QM results to classical physics, but were usually used to determine QM selection rules from classical physics. ...
The Weird World of Quantum Information
... Initialization: ability to prepare one certain state repeatedly on demand, for example put all to zero at the start. Ability to perform (universal) logical operations. No or very small error rate (that can be fixed). Ability to efficiently read out the result. ...
... Initialization: ability to prepare one certain state repeatedly on demand, for example put all to zero at the start. Ability to perform (universal) logical operations. No or very small error rate (that can be fixed). Ability to efficiently read out the result. ...
Chapter 13 – Electrons in Atoms
... Electron Arrangement in Atoms Physics and the Quantum Mechanical Model ...
... Electron Arrangement in Atoms Physics and the Quantum Mechanical Model ...
preview
... world. One of the most significant of these developments was the replacement of the classical physics of Newton, Maxwell, and Einstein with the quantum physics of Planck, Bohr, and Heisenberg. Usually our understanding of the universe grows at an agonizingly slow pace. For example, a group of scient ...
... world. One of the most significant of these developments was the replacement of the classical physics of Newton, Maxwell, and Einstein with the quantum physics of Planck, Bohr, and Heisenberg. Usually our understanding of the universe grows at an agonizingly slow pace. For example, a group of scient ...
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.