33 research outputs found
Inversion of Gamow's Formula and Inverse Scattering
We present a pedagogical description of the inversion of Gamow's tunnelling
formula and we compare it with the corresponding classical problem. We also
discuss the issue of uniqueness in the solution and the result is compared with
that obtained by the method of Gel'fand and Levitan. We hope that the article
will be a valuable source to students who have studied classical mechanics and
have some familiarity with quantum mechanics.Comment: LaTeX, 6 figurs in eps format. New abstract; notation in last
equation has been correcte
Theory of Polaron Resonance in Quantum Dots and Quantum-Dot Molecules
The theory of exciton coupling to photons and LO phonons in quantum dots
(QDs) and quantum-dot molecules (QDMs) is presented. Resonant-round trips of
the exciton between the ground (bright) and excited (dark or bright) states
mediated by the LO-phonon alter the decay time and yield the Rabi oscillation.
The initial distributions of the population in the ground and the excited
states dominate the oscillating amplitude and frequency. This property provides
a detectable signature to the information stored in a qubit made from QD or QDM
for a wide range of temperature T. Our results presented herein provide an
explanation to the anomaly on T-dependent decay in self-assembled InGaAs/GaAs
QDMs recently reported by experiment.Comment: 30 pages, 8 figure
SU(3) symmetry breaking in decay constants and electromagnetic properties of pseudoscalar heavy mesons
In this paper, the decay constants and mean square radii of pseudoscalar
heavy mesons are studied in the SU(3) symmetry breaking. Within the light-front
framework, the ratios and are individually
estimated using the hyperfine splittings in the and
states and the light quark masses, (), to
extract the wave function parameter . The values and are obtained, which are not only
chiefly determined by the ratio of light quark masses , but also
insensitive to the heavy quark masses and the decay constants
. The dependence of on with the
varied charm quark masses is also shown. In addition, the mean square radii are
estimated as well. The values and are obtained, and the sensitivities of on
the heavy and light quark masses are similar to those of the decay constants.Comment: 21 pages, 5 figures, 4 tables, some typos are corrected, version to
be published in Phys. Rev.
Local entanglement of multidimensional continuous-variable systems
We study the `local entanglement' remaining after filtering operations
corresponding to imperfect measurements performed by one or both parties, such
that the parties can only determine whether or not the system is located in
some region of space. The local entanglement in pure states of general
bipartite multidimensional continuous-variable systems can be completely
determined through simple expressions. We apply our approach to semiclassical
WKB systems, multi-dimensional harmonic oscillators, and a hydrogen atom as
three examples.Comment: RevTex, 11 pages, 3 figures (13 files
Magneto-optics of quasirelativistic electrons in graphene with an inplane electric field and in tilted Dirac cones in α
Theory and numerical modelling of parity-time symmetric structures in photonics: introduction and grating structures in one dimension
A class of structures based on PT PT-symmetric Bragg gratings in the presence of both gain and loss is studied. The basic concepts and properties of parity and time reversal in one-dimensional structures that possess idealised material properties are given. The impact of realistic material properties on the behaviour of these devices is then investigated. Further extension to include material non-linearity is used to study an innovative all-optical
memory device