Quantum Phenomena in Condensed Phase
... lation and coherences in the representation of the density matrix, or “surface hopping” trajectories. We implement this on model condensed phase systems and compare results with a path-integral approach that is linearized in the forward and backward bath variables, developed and coded previously in ...
... lation and coherences in the representation of the density matrix, or “surface hopping” trajectories. We implement this on model condensed phase systems and compare results with a path-integral approach that is linearized in the forward and backward bath variables, developed and coded previously in ...
Nobel Lecture: Fractional quantization
... virtue of the Peierls effect. The gapped electron spectrum shown in Fig. 2 is the density of states for ␦ ⫽0.1. When the equation is solved again for the soliton one finds an extra state in the center of the gap. The soliton has charge ⫹e when this state is unoccupied. The remaining charge and spin ...
... virtue of the Peierls effect. The gapped electron spectrum shown in Fig. 2 is the density of states for ␦ ⫽0.1. When the equation is solved again for the soliton one finds an extra state in the center of the gap. The soliton has charge ⫹e when this state is unoccupied. The remaining charge and spin ...
Level Repulsion of Localized Excitons in Disordered Quantum Wells
... we simulate the optical density spectrum, which under the present conditions is expected to provide the same information as the PL spectrum [10]. The quantity RðDEÞ represents the average distribution of energy-level distances weighted by the optical strengths, while R0 ðDEÞ is its uncorrelated coun ...
... we simulate the optical density spectrum, which under the present conditions is expected to provide the same information as the PL spectrum [10]. The quantity RðDEÞ represents the average distribution of energy-level distances weighted by the optical strengths, while R0 ðDEÞ is its uncorrelated coun ...
Phys. Rev. Lett. 98, 070602
... becomes equivalent to the ‘‘even’’ Ising gauge theory, the emergent gauge theory description of the quantum dimer model [13]. The low-energy sector has no free charges and any state is described by a collection of loops that can be obtained from a reference state (e.g., all zi 1=2) by a sequence ...
... becomes equivalent to the ‘‘even’’ Ising gauge theory, the emergent gauge theory description of the quantum dimer model [13]. The low-energy sector has no free charges and any state is described by a collection of loops that can be obtained from a reference state (e.g., all zi 1=2) by a sequence ...
Rydberg assisted light shift imbalance induced blockade in an atomic ensemble ,
... between two ensembles, necessary for realizing a quantum computer, must make use of additional, classical laser fields. Under such excitations, an ensemble no longer behaves like a two-level system. Instead, it exhibits a cascade of energy levels that are equally spaced. When exposed to a classical fi ...
... between two ensembles, necessary for realizing a quantum computer, must make use of additional, classical laser fields. Under such excitations, an ensemble no longer behaves like a two-level system. Instead, it exhibits a cascade of energy levels that are equally spaced. When exposed to a classical fi ...
Testing the Symmetrization Postulate of Quantum Mechanics and
... be symmetric in the exchange of two nuclei. Since the nuclear spin is zero, wn is obviously symmetric. The vibrational wave function wv is also unaltered in the exchange of the nuclei because it depends only on the magnitude of the internuclear distance. Since the total wavefunction wt must be symme ...
... be symmetric in the exchange of two nuclei. Since the nuclear spin is zero, wn is obviously symmetric. The vibrational wave function wv is also unaltered in the exchange of the nuclei because it depends only on the magnitude of the internuclear distance. Since the total wavefunction wt must be symme ...
1. Introduction - Université de Rennes 1
... Let us now make a remark. One can see on the formula (1.1) that the quantum Maxwellian reads as the global equilibrium canonical ensemble associated to the Hamiltonian −∆ + A(x), where the chemical potential A(x) is seen as an applied potential. Hence, our problem can be reformulated as the followin ...
... Let us now make a remark. One can see on the formula (1.1) that the quantum Maxwellian reads as the global equilibrium canonical ensemble associated to the Hamiltonian −∆ + A(x), where the chemical potential A(x) is seen as an applied potential. Hence, our problem can be reformulated as the followin ...
Computing with Highly Mixed States
... —Generally, it is important to allow for errors in the gates of the quantum computer. Since this article is primarily concerned with a lower bound, we allow error-free gates. —The output of the algorithm is obtained by measuring one or more qubits of the quantum register in the standard basis. Of co ...
... —Generally, it is important to allow for errors in the gates of the quantum computer. Since this article is primarily concerned with a lower bound, we allow error-free gates. —The output of the algorithm is obtained by measuring one or more qubits of the quantum register in the standard basis. Of co ...
Propagation of double Rydberg wave packets F Robicheaux and R C Forrey doi:10.1088/0953-4075/38/2/027
... the electrons are on opposite sides of the nucleus. The results in figure 2 are for nRyd ∼ 10 and in figure 3 are for nRyd ∼ 15. The times are given in increments of τRyd /5 and the radial scales have been chosen to roughly reflect the n2Ryd distance scaling. While there is clearly electron probabil ...
... the electrons are on opposite sides of the nucleus. The results in figure 2 are for nRyd ∼ 10 and in figure 3 are for nRyd ∼ 15. The times are given in increments of τRyd /5 and the radial scales have been chosen to roughly reflect the n2Ryd distance scaling. While there is clearly electron probabil ...
ΟΝ THE WAVE FUNCTION OF THE PHOTON
... This integral operator changes the dimension from L -2 to L -3 / 2 , so that the modulus squared of the Landau-Peierls wave function may be interpreted as a probability density to fmd a photon. However, as has been already noted by Pauli [12], these nonlocal wave functions have serious drawbacks. Fi ...
... This integral operator changes the dimension from L -2 to L -3 / 2 , so that the modulus squared of the Landau-Peierls wave function may be interpreted as a probability density to fmd a photon. However, as has been already noted by Pauli [12], these nonlocal wave functions have serious drawbacks. Fi ...
(PPT, Unknown) - Natural Philosophy Alliance
... • Anti – submarine indicator loops on the sea floor acted as a warning system for approaching submarines in WW 2 • The heart’s magnetic field is well documented. Tell tale fluctuations in the magnetic field of the heart can be monitored real time using magnetic biosensors • Superconducting loops in ...
... • Anti – submarine indicator loops on the sea floor acted as a warning system for approaching submarines in WW 2 • The heart’s magnetic field is well documented. Tell tale fluctuations in the magnetic field of the heart can be monitored real time using magnetic biosensors • Superconducting loops in ...
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.