312 research outputs found
Dynamic method to distinguish between left- and right-handed chiral molecules
We study quantum systems with broken symmetry that can be modelled as cyclic
three-level atoms with coexisting one- and two-photon transitions. They can be
selectively optically excited to any state. As an example, we show that left-
and right-handed chiral molecules starting in the same initial states can
evolve into different final states by a purely dynamic transfer process. That
means, left- and right-handed molecules can be distinguished purely
dynamically.Comment: 4 pages, submitted to Phys. Rev.
On the Symmetric Space Sigma-Model Kinematics
The solvable Lie algebra parametrization of the symmetric spaces is
discussed. Based on the solvable Lie algebra gauge two equivalent formulations
of the symmetric space sigma model are studied. Their correspondence is
established by inspecting the normalization conditions and deriving the field
transformation laws.Comment: 17 page
Embedded Gaussian Unitary Ensembles with Embedding generated by Random Two-body Interactions with Symmetry
Following the earlier studies on embedded unitary ensembles generated by
random two-body interactions [EGUE(2)] with spin SU(2) and spin-isospin SU(4)
symmetries, developed is a general formulation, for deriving lower order
moments of the one- and two-point correlation functions in eigenvalues, that is
valid for any EGUE(2) and BEGUE(2) ('B' stands for bosons) with embedding and with two-body interactions preserving
symmetry. Using this formulation with , we recover the results derived by
Asaga et al [Ann. Phys. (N.Y.) 297, 344 (2002)] for spinless boson systems.
Going further, new results are obtained for (this corresponds to two
species boson systems) and (this corresponds to spin 1 boson systems).Comment: 25 pages, 7 figure
Unified description of 0+ states in a large class of nuclear collective models
A remarkably simple regularity in the energies of 0+ states in a broad class
of collective models is discussed. A single formula for all 0+ states in
flat-bottomed infinite potentials that depends only on the number of dimensions
and a simpler expression applicable to all three IBA symmetries in the large
boson number limit are presented. Finally, a connection between the energy
expression for 0+ states given by the X(5) model and the predictions of the IBA
near the critical point is explored.Comment: 4 pages, 3 postscript figures, uses revTe
On Supermultiplet Twisting and Spin-Statistics
Twisting of off-shell supermultiplets in models with 1+1-dimensional
spacetime has been discovered in 1984, and was shown to be a generic feature of
off-shell representations in worldline supersymmetry two decades later. It is
shown herein that in all supersymmetric models with spacetime of four or more
dimensions, this off-shell supermultiplet twisting, if non-trivial, necessarily
maps regular (non-ghost) supermultiplets to ghost supermultiplets. This feature
is shown to be ubiquitous in all fully off-shell supersymmetric models with
(BV/BRST-treated) constraints.Comment: Extended version, including a new section on manifestly off-shell and
supersymmetric BRST treatment of gauge symmetry; added reference
Structure of the doublet bands in doubly odd nuclei: The case of
The structure of the doublet bands in is
investigated within the framework of the Interacting Vector Boson Fermion Model
(IVBFM). A new, purely collective interpretation of these bands is given on the
basis of the used boson-fermion dynamical symmetry of the model. The energy
levels of the doublet bands as well as the absolute and
transition probabilities between the states of both yrast and yrare bands are
described quite well. The observed odd-even staggering of both and
values is reproduced by the introduction of an appropriate interaction
term of quadrupole type, which produces such a staggering effect in the
transition strengths. The calculations show that the appearance of doublet
bands in certain odd-odd nuclei could be a consequence of the realization of a
larger dynamical symmetry based on the non-compact supersymmetry group
.Comment: 12 pages, 8 figure
Conformal symmetry and light flavor baryon spectra
The degeneracy among parity pairs systematically observed in the N and Delta
spectra is interpreted to hint on a possible conformal symmetry realization in
the light flavor baryon sector in line with AdS_5/CFT_4. The case is made by
showing that all the observed N and Delta resonances with masses below 2500 MeV
distribute fairly well each over the first levels of a unitary representation
of the conformal group, a representation that covers the spectrum of a
quark-diquark system, placed directly on the AdS_5 cone, conformally
compactified to R^1*S^3. The free geodesic motion on the S^3 manifold is
described by means of the scalar conformal equation there, which is of the
Klein-Gordon type. The equation is then gauged by the "curved" Coulomb
potential that has the form of a cotangent function. Conformal symmetry is not
exact, this because the gauge potential slightly modifies the conformal
centrifugal barrier of the free geodesic motion. Thanks to this, the degeneracy
between P11-S11 pairs from same level is relaxed, while the remaining states
belonging to same level remain practically degenerate. The model describes the
correct mass ordering in the P11-S11 pairs through the nucleon spectrum as a
combined effect of the above conformal symmetry breaking, on the one side, and
a parity change of the diquark from a scalar at low masses, to a pseudoscalar
at higher masses, on the other. The quality of the wave functions is
illustrated by calculations of realistic mean-square charge radii and electric
charge form-factors on the examples of the proton, and the protonic P11(1440),
and S11(1535) resonances. The scheme also allows for a prediction of the
dressing function of an effective instantaneous gluon propagator from the
Fourier transform of the gauge potential. We find a dressing function that is
finite in the infrared and tends to zero at infinity.Comment: Latex, 5 figures, 2 tables; Paper upgraded in accord with the
published version. Discussion on the meson sector include
Correlated Photons from Collective Excitations of Three-Level Atomic Ensemble
We systematically study the interaction between two quantized optical fields
and a cyclic atomic ensemble driven by a classic optical field. This so-called
atomic cyclic ensemble consists of three-level atoms with Delta-type
transitions due to the symmetry breaking, which can also be implemented in the
superconducting quantum circuit by Yu-xi Liu et al. [Phys. Rev. Lett. 95,
087001 (2005)]. We explore the dynamic mechanisms to creating the quantum
entanglements among photon states, and between photons and atomic collective
excitations by the coherent manipulation of the atom-photon system. It is shown
that the quantum information can be completely transferred from one quantized
optical mode to another, and the quantum information carried by the two
quantized optical fields can be stored in the collective modes of this atomic
ensemble by adiabatically controlling the classic field Rabi frequencies.Comment: 10 pages, 2 figure
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