12 research outputs found
Multi-site Integrated Optical Addressing of Trapped Ions
One of the most effective ways to advance the performance of quantum
computers and quantum sensors is to increase the number of qubits or quantum
resources used by the system. A major technical challenge that must be solved
to realize this goal for trapped-ion systems is scaling the delivery of optical
signals to many individual ions. In this paper we demonstrate an approach
employing waveguides and multi-mode interferometer splitters to optically
address multiple ions in a surface trap by delivering all
wavelengths required for full qubit control. Measurements of hyperfine
spectroscopy and Rabi flopping were performed on the E2 clock transition, using
integrated waveguides for delivering the light needed for Doppler cooling,
state preparation, coherent operations, and detection. We describe the use of
splitters to address multiple ions using a single optical input per wavelength
and use them to demonstrate simultaneous Rabi flopping on two different
transitions occurring at distinct trap sites. This work represents an important
step towards the realization of scalable integrated photonics for atomic clocks
and trapped-ion quantum information systems.Comment: 7 pages, 4 figures (+2 supplementary figures
A natural little hierarchy for RS from accidental SUSY
We use supersymmetry to address the little hierarchy problem in
Randall-Sundrum models by naturally generating a hierarchy between the IR scale
and the electroweak scale. Supersymmetry is broken on the UV brane which
triggers the stabilization of the warped extra dimension at an IR scale of
order 10 TeV. The Higgs and top quark live near the IR brane whereas light
fermion generations are localized towards the UV brane. Supersymmetry breaking
causes the first two sparticle generations to decouple, thereby avoiding the
supersymmetric flavour and CP problems, while an accidental R-symmetry protects
the gaugino mass. The resulting low-energy sparticle spectrum consists of
stops, gauginos and Higgsinos which are sufficient to stabilize the little
hierarchy between the IR scale and the electroweak scale. Finally, the
supersymmetric little hierarchy problem is ameliorated by introducing a singlet
Higgs field on the IR brane.Comment: 37 pages, 3 figures; v2: minor corrections, version published in JHE
nu Seesaw Uses: UV Insensitive Supersymmetry Breaking without Tachyons
This document contains a systematic analysis of supersymmetric left-right models in the context of anomaly mediated supersymmetry breaking starting with the high-scale, left-right theory and ending with the supersymmetry-scale theory. It is shown that the combination of supersymmetric left-right models and anomaly mediated supersymmetry breaking retains the attractive features of anomaly mediation while simultaneously providing a solution to the tachyonic slepton problem of the minimal supersymmetric standard model with anomaly mediated supersymmetry breaking.
The supersymmetric left-right theory introduces new yukawa couplings that permit positive slepton mass-squares while retaining the ultra violet insensitivity of anomaly mediated supersymmetry breaking as well its economy. The new couplings are introduced by independent considerations of explaining neutrino oscillation experiments through the seesaw mechanism, and survive below the seesaw scale from an accidental symmetry of the potential. Furthermore, the seesaw mechanism is implemented in such a way that R-parity is a natural residual symmetry--leading to a stable, weakly-interacting particle to explain dark matter.
The resulting mass spectrum is detailed, both qualitatively and quantitatively, providing comparisons with other popular supersymmetry breaking scenarios. It is demonstrated that the model contains gaugino masses that are much closer in size than other schemes, as well as the possibility of a mild squark-slepton mass degeneracy. The issue of higgsino masses is also explored, and attention is paid to the dark matter composition. The model is shown to have a viable dark matter candidate that evades current direct detection bounds but will be probed by future planned experiments.
The low-energy consequences of the model are analyzed, and the matter of electroweak symmetry breaking is expounded. It is shown that the problem of a higgsino mass below the LEP II bound in the next-to minimal supersymmetric standard model with anomaly mediated supersymmetry breaking is easily avoided by this theory. Finally, prospects for confirmation of this theory at the LHC are investigated, as well as potential signatures in lepton flavor violation experiments