1,273 research outputs found
Comparisons and Combinations of Reactor and Long-Baseline Neutrino Oscillation Measurements
We investigate how the data from various future neutrino oscillation
experiments will constrain the physics parameters for a three active neutrino
mixing model. The investigations properly account for the degeneracies and
ambiguities associated with the phenomenology as well as estimates of
experimental measurement errors. Combinations of various reactor measurements
with the expected J-PARC (T2K) and NuMI offaxis (Nova) data, both with and
without the increased flux associated with proton driver upgrades, are
considered. The studies show how combinations of reactor and offaxis data can
resolve degeneracies (e.g. the theta23 degeneracy) and give more precise
information on the oscillation parameters. A primary purpose of this
investigation is to establish the parameter space regions where CP violation
can be discovered and where the mass hierarchy can be determined. It is found
that such measurements, even with the augmented flux from proton driver
upgrades, demand sin^2 (2 theta13) be fairly large and in the range where it is
measurable by reactor experiments.Comment: 25 pages, 13 figures, fixed typos; 25 pages, 13 figures, updated
content, references; previous 22 pages, 12 figures, added references and
fixed reference display proble
Large-Scale Schr\"odinger-Cat States and Majorana Bound States in Coupled Circuit-QED Systems
We have studied the low-lying excitations of a chain of coupled circuit-QED
systems, and report several intriguing properties of its two nearly degenerate
ground states. The ground states are Schr\"odinger cat states at a truly large
scale, involving maximal entanglement between the resonator and the qubit, and
are mathematically equivalent to Majorana bound states. With a suitable design
of physical qubits, they are protected against local fluctuations and
constitute a non-local qubit. Further, they can be probed and manipulated
coherently by attaching an empty resonator to one end of the circuit-QED chain.Comment: 5 pages; 2 figures; incorrect references corrected; typos correcte
Variational study of a two-level system coupled to a harmonic oscillator in a ultrastrong coupling regime
The nonclassical behaviors of a two-level system coupled to a harmonic
oscillator is investigated in the ultrastrong coupling regime. We revisit the
variational solution of the ground state and find that the existing solution do
not account accurately for nonclassical effects such squeezing. We suggest a
new trial wave function and demonstrate that it has an excellent accuracy on
the quantum correlation effects as well as on energy.Comment: 4 pages; 3 figures; to appear in Phys. Rev.
Spatiotemporal Stochastic Resonance in Fully Frustrated Josephson Ladders
We consider a Josephson-junction ladder in an external magnetic field with
half flux quantum per plaquette. When driven by external currents, periodic in
time and staggered in space, such a fully frustrated system is found to display
spatiotemporal stochastic resonance under the influence of thermal noise. Such
resonance behavior is investigated both numerically and analytically, which
reveals significant effects of anisotropy and yields rich physics.Comment: 8 pages in two columns, 8 figures, to appear in Phys. Rev.
Decoherence Driven Quantum Transport
We propose a new mechanism to generate a dc current of particles at zero bias
based on a noble interplay between coherence and decoherence. We show that a dc
current arises if the transport process in one direction is maintained coherent
while the process in the opposite direction is incoherent. We provide possible
implementations of the idea using an atomic Michelson and an atomic
Aharonov-Bohm interferometer.Comment: 4 pages, 3 figure
- …