920 research outputs found
Practical tracking control for stochastic nonlinear systems with polynomial function growth conditions
This paper mainly focuses on an output feedback practical tracking controller design for a class of stochastic nonlinear systems with polynomial function growth conditions. Mostly, there are some studies on an output feedback tracking control problem for general nonlinear systems with polynomial function growth conditions in existing achievements. Moreover, we extend it to stochastic nonlinear systems and construct an output feedback practical tracking controller based on dynamic and static phase combined, ensuring that all the states of the stochastic nonlinear system are bounded and the system tracking error can be made arbitrarily small after some large enough time. Finally, a simulation example is provided to illustrate the efficiency of the theoretical results
Microwave transmission through an artificial atomic chain coupled to a superconducting photonic crystal
Emitters strongly coupled to a photonic crystal provide a powerful platform
for realizing novel quantum light-matter interactions. Here we study the
optical properties of a three-level artificial atomic chain coupled to a
one-dimensional superconducting microwave photonic crystal. A sharp
minimum-energy dip appears in the transmission spectrum of a weak input field,
which reveals rich behavior of the long-range interactions arising from
localized bound states. We find that the dip frequency scales linearly with
both the number of the artificial atoms and the characteristic strength of the
long-range interactions when the localization length of the bound state is
sufficiently large. Motivated by this observation, we present a simple model to
calculate the dip frequency with system parameters, which agrees well with the
results from exact numerics for large localization lengths. We observe
oscillation between bunching and antibunching in photon-photon correlation
function of the output field. Furthermore, we find that the model remains valid
even though the coupling strengths between the photonic crystal and artificial
atoms are not exactly equal and the phases of external driving fields for the
artificial atoms are different. Thus, we may infer valuable system parameters
from the dip location in the transmission spectrum, which provides an important
measuring tool for the superconducting microwave photonic crystal systems in
experiment. With remarkable advances to couple artificial atoms with microwave
photonic crystals, our proposal may be experimentally realized in currently
available superconducting circuits.Comment: 10 pages, 7 figure
Prime Factorization in the Duality Computer
We give algorithms to factorize large integers in the duality computer. We
provide three duality algorithms for factorization based on a naive
factorization method, the Shor algorithm in quantum computing, and the Fermat's
method in classical computing. All these algorithms are polynomial in the input
size.Comment: 4 page
A new model to predict the unsteady production of fractured horizontal wells
Based on the hydraulic fracture width gradually narrows along the fracture length, with consideration of the mutual influences of fracture, non-uniform inflow of fractures segments and variable mass flow in the fracture comprehensively, a spatial separation method and time separation method were used to establish fracture horizontal wellâs dynamic coupling model of reservoir seepage and fracture flow. The results showed that the calculation productivity of variable width model is higher than that of the fixed width model, while the difference becomes smaller as time increase. Due to mutual interference of the fractures, the production of outer fracture is higher than that of the inner fracture. When the dimensionless fracture conductivity is 0.1, the middle segment of the fracture dominates the productivity and local peak emerges near the horizontal well. The flow in the fracture is with the âdouble Uâ type distribution. As the dimensionless fracture conductivity increase, the fractures productivity mainly through the tips and the flow in the fractures with the âUâ type distribution. Using the established fracture width variable productivity prediction model, one can achieve the quantitative optimization of fracture shape
Revisiting Bohr's principle of complementarity using a quantum device
Bohr's principle of complementarity lies at the central place of quantum
mechanics, according to which the light is chosen to behave as a wave or
particles, depending on some exclusive detecting devices. Later, intermediate
cases are found, but the total information of the wave-like and particle-like
behaviors are limited by some inequalities. One of them is Englert-Greenberger
(EG) duality relation. This relation has been demonstrated by many experiments
with the classical detecting devices. Here by introducing a quantum detecting
device into the experiment, we find the limit of the duality relation is
exceeded due to the interference between the photon's wave and particle
properties. However, our further results show that this experiment still obey a
generalized EG duality relation. The introducing of the quantum device causes
the new phenomenon, provides an generalization of the complementarity
principle, and opens new insights into our understanding of quantum mechanics.Comment: 5 pages, 4 figure
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