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Showing 1 to 13 of 13 for “"Wigner function"”.
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Wigner functions for a class of semidirect product groups
We define and construct Wigner functions for the class of semidirect product groups [Special characters omitted.] whose linear part H ✹ GL ( n , [Special characters omitted.] ) is a closed Lie subgroup of GL ( n , [Special characters omitted.] ) admitting at least one open and free orbit in …
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Phase space methods in finite quantum systems.
… is introduced. In this phase space the extended Wigner and Weyl functions are defined and their marginal properties are studied. The fourth order interference in the extended phase space is studied and verified using the extended Wigner function. It is seen that for both pure and mixed states the …
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Quantum mechanics on phase space : geometry and motion of the Wigner distribution
We study the Wigner phase space formulation of quantum mechanics and compare it to the Hamiltonian picture of classical mechanics. In this comparison we focus on the differences in initial conditions available to each theory as well as the differences in dynamics. First we derive new necessary …
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Generation and Measurement of Entangled Atomic Ensembles with an Optical Cavity
… atom-cavity interaction, we construct a negative Wigner function, manifestly demonstrating that the atoms are entangled. We also show that nearly all of 3000 atoms are involved in the entanglement using an entanglement measure known as the entanglement depth.
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ρ^' Photoproduction in ultra- peripheral heavy ion collisions with the ALICE detector
… distribution was fit with both a single Breit-Wigner function, to compare with the results obtained by the STAR collaboration and with a combination of two Breit-Wigner functions, as expected based on the Particle Data Group. The results I obtained favors the two Breit-Wigner interpretation, …
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Phase space and path integral approaches to quantum dynamics
… methods for calculating the multidimensional Wigner function. We start with a simple and approximate method which utilizes classical trajectories. This fits well with the subsequent classical propagation involved in a quasiclassical simulation. We use this method to study molecular …
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Light-induced many-body correlations in ultracold gases
… the first observation of the negative Wigner function in the many-body system, and largely extended the record of the maximum number of atoms entangled. Other than engineering entangled many-body system, we have also worked on reaching the quantum degenerate regime for the atomic gas, …
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Quantization of Chirikov map and quantum KAM theorem
… operator of this system. We find that the wave functions in the coherent state representation (CSR) are very similar to the classical trajectories. In particular, some of these wave functions have wall-like structure at the locations of classical KAM curves. We also find that a local average is …
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Correlated electron transport across atomic and molecular tunnel junctions
… such as NEGF+DFT non-equilibrium Green’s function plus density functional theory. Typical single particle treatments are incomplete due to approximations made in the treatment of the electronic structure leading to discrepancies between theory and experiment by orders of magnitude, …
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Schrödinger equation with periodic potentials.
… maximum value of the potential, are presented. Wigner and Weyl functions, corresponding to the solutions of Schrödinger equation, are also studied. It is also shown that they are very sensitive to the value of the parameter y.
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Advanced waveguides for high power optical fibre sources
… is based on a tomography technique that uses a Wigner function followed by an inverse Radon transform. The second method adopts a wavelength-sweeping optical source which induces beat patterns after propagation through a certain length of fibre. The feasibilities of the two proposed ideas were …
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Bi-fractional transforms in phase space
… with respect to the density operator gives the Wigner functions (displaced parity operator) and Weyl functions (displacement operator). The generalisation of the parity-displacement operator relationship considered here is called the bi-fractional displacement operator, O(α, β; θα, θβ). …
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ΘΕΩΡΙΑ ΤΟΥ ΦΑΣΙΚΟΥ ΧΩΡΟΥ ΤΗΣ ΜΗ-ΑΡΝΗΤΙΚΗΣ ΣΥΝΑΡΤΗΣΗΣ ΚΑΤΑΝΟΜΗΣ ΤΥΠΟΥ WIGNER
THE PROBLEM OF THE NON-NEGATIVE WIGNER DISTRIBUTION FUNCTION IS STUDIED. IT HASBEEN RECOGNIZED THAT THE PROBLEM IS RELATED TO SOME RECOGNIZED CORRESPODENSE RULE. THE NEW WIGNER DISTRIBUTION FUNCTION IS CONNECTED TO THE HUSIMI TRANSFORMATION AND AS IT IS PROVED TAKES CLOSED FORM, WHILE AT THE SAME …