mahmoud.abdelatty

محمود محمد أحمد عبدالعاطى

استاذ - أستاذ

كلية العلوم

العنوان: Sohag, 15 Str

17

إعجاب
2010 | الكلمات المفتاحية dissipative cavities, entanglement sudden death, lived entanglement,
Two atoms in dissipative cavities in dispersive limit: entanglement sudden death and long-lived entanglement
We investigate the entanglement dynamics and coherence of two two-level atoms interacting with two coherent fields of two spatially separated and dissipative cavities. It is in particular shown that entanglement sudden death is obtained within a short interaction time. However, after a long interaction time a long-lived entanglement is shown; that is, the initial entanglement of two atoms could be ... إقراء المزيد

2009 | الكلمات المفتاحية nondemolition, Cavity QED, quantized atomic motion,
Cavity QED nondemolition measurement scheme using quantized atomic motion
Considering ultracold atoms traversing a high-Q Fabry-Pérot cavity, we theoretically demonstrate a quantum nondemolition measurement of the photon number. This fully quantum mechanical approach may be understood utilizing concepts as effective mass and group velocity of the atom. The various photon numbers induce a splitting of the atomic wave packet, and a time-of-flight measurement of the atom thereby reveals the ... إقراء المزيد

2009 | الكلمات المفتاحية Phase control, PANCHARATNAM PHASE,
Phase control of the Pancharatnam phase
We propose a method to control the atomic dynamics in the presence of electromagnetic fields. Instead of measuring the population dynamics, we focus on the possibility of controlling the Pancharatnam phase. For a two-level system we find that this phase can be optically induced and controlled by the phase shift. More importantly, the nonlinear interaction between the atom and the ... إقراء المزيد

2009 | الكلمات المفتاحية Berry phase, qubits, a Cavity Field,
Berry phase in superconducting charge qubits interacting with a cavity field
We propose a method for analyzing Berry phase for a multi-qubit system of superconducting charge qubits interacting with a microwave field. By suitably choosing the system parameters and precisely controlling the dynamics, novel connection found between the Berry phase and entanglement creations. إقراء المزيد

2009 | الكلمات المفتاحية Perspectives, Qubit, bimodal cavity fields,
Perspectives for a superconducting charge qubit system interacting with bimodal cavity fields
We report on the observation of new features in a superconducting charge qubit system. The system we analyze comprises of a single Cooper-pair box sequentially coupled to two microwave cavity fields. Simulations of the full qubit–field dynamics show significant total correlation and coherence loss. By suitably choosing the system’s parameters and precisely controlling the dynamics, we demonstrate the generation of ... إقراء المزيد

2009 | الكلمات المفتاحية light processes, Theoretical study,
Slowing and storing light processes without a trapping dark state in a double two-level system. Theoretical study
We present a detailed theoretical study of a method for slowing light based on the oscillations of Zeeman coherences in a double two-level system [Hashmi, F.A.; Bouchene, M.A. _Phys. Rev. A_ 2008, _77_, 051803(R)]. This method does not require the presence of any trapping state. We focus on the properties and the limitations of such a method and compare it ... إقراء المزيد

2009 | الكلمات المفتاحية sudden birth, sudden death, Entanglement,
Delayed sudden birth and sudden death of entanglement in Josephson-charge qubits
Distinctive features of the entanglement dynamics of a circuit containing two-coupled superconducting charge qubits are explored. The striking effects of junction coupling on the entanglement are presented in terms of the concurrence. We also point out the importance effects of initial state selection for obtaining different features of entanglement, such as, sudden death and sudden birth. إقراء المزيد

2009 | الكلمات المفتاحية Tripartite, entanglement dynamics, nonlinear couplers,
Tripartite entanglement dynamics for an atom interacting with nonlinear couplers
In this communication we introduce a new model which represents the interaction between an atom and two fields injected simultaneously within a cavity including the nonlinear couplers. By using the canonical transformation the model can be regarded as a generalization of several well-known models. We calculate and discuss entanglement between the tripartite system of one atom and the two cavity ... إقراء المزيد

2009 | الكلمات المفتاحية Bloch vectors, channel capacity, non-identical charge qubits,
Dynamics of Bloch vectors and channel capacity of two non-identical charge qubits
We have considered a system of two superconducting charge qubits capacitively coupled to a microwave resonator. By means of the Bloch vectors and cross dyadic we quantify the degree of entanglement contained in the generated entangled state in different regimes. We show the important roles played by initial state settings, coupling constant and the mean photon number on generating entangled ... إقراء المزيد

2009 | الكلمات المفتاحية phonon trap modes, three-level trapped, Entanglement,
Entanglement of three-level trapped ions with phonon trap modes
The entanglement between a single electron in the electronic states of a trapped three-level ion and the ionic vibrational modes of the trap is studied for an initially unentangled state of an electron level and a coherent phonon state. The effects of time-independent and time-dependent couplings are discussed. إقراء المزيد