154,441 research outputs found
Physical mechanisms governing pattern fidelity in microscale offset printing
We have studied the offset printing of liquid polymers curable by exposure to ultraviolet light onto flat and unpatterned silicon and glass substrates. The interplay of capillary, viscous, and adhesion forces dominates the dynamics of ink transfer at small feature sizes and low capillary number. For smooth and nonporous substrates, pattern fidelity can be compromised because the ink contact lines are free to migrate across the substrate during plate separation. Using a combination of experiments and equilibrium simulations, we have identified the physical mechanisms controlling ink transfer and pattern fidelity. In considering the resolution limit of this technique, it appears that the dynamics of ink flow and redistribution during transfer do not explicitly depend on the absolute feature size, but only on the aspect ratio of film thickness to feature size. Direct printing holds promise as a high-throughput fabrication method for large area electronics
State transfer in dissipative and dephasing environments
By diagonalization of a generalized superoperator for solving the master
equation, we investigated effects of dissipative and dephasing environments on
quantum state transfer, as well as entanglement distribution and creation in
spin networks. Our results revealed that under the condition of the same
decoherence rate , the detrimental effects of the dissipative
environment are more severe than that of the dephasing environment. Beside
this, the critical time at which the transfer fidelity and the
concurrence attain their maxima arrives at the asymptotic value
quickly as the spin chain length increases. The transfer
fidelity of an excitation at time is independent of when the system
subjects to dissipative environment, while it decreases as increases when
the system subjects to dephasing environment. The average fidelity displays
three different patterns corresponding to , and . For
each pattern, the average fidelity at time is independent of when the
system subjects to dissipative environment, and decreases as increases when
the system subjects to dephasing environment. The maximum concurrence also
decreases as increases, and when , it arrives at an
asymptotic value determined by the decoherence rate and the structure
of the spin network.Comment: 12 pages, 6 figure
Direct printing of polymer microstructures on flat and spherical surfaces using a letterpress technique
We have developed a letterpress technique capable of printing polymer films with micrometer scale feature sizes onto flat or spherically shaped nonporous substrates. This printing technique deposits polymer only in desired regions thereby eliminating subsequent developing and subtraction steps. Flat or curved printing plates, which are fabricated from either rigid or deformable materials, are used to transfer thin molten polymer films onto flat target substrates. By deforming the printing plates into a spherical shape, it is also possible to print patterned films onto the concave side of a spherically deformed target substrate. These printed films serve as good resists for both wet chemical etching and reactive ion etching. Interferometric measurements of the polymer film thickness are used to probe physical mechanisms affecting printing instabilities, pattern fidelity, and edge resolution. Our experimental study indicates that this letterpress technique may prove suitable for high-throughput device fabrication involving large-area microelectronics
Quantum-state transfer in staggered coupled-cavity arrays
We consider a coupled-cavity array, where each cavity interacts with an atom under the rotating-wave approximation. For a staggered pattern of inter-cavity couplings, a pair of field normal modes each bi-localized at the two array ends arise. A rich structure of dynamical regimes can hence be addressed depending on which resonance condition between the atom and field modes is set. We show that this can be harnessed to carry out high-fidelity quantum-state transfer (QST) of photonic, atomic or polaritonic states. Moreover, by partitioning the array into coupled modules of smaller length, the QST time can be substantially shortened without significantly affecting the fidelity
Quantum-state transfer in staggered coupled-cavity arrays
We consider a coupled-cavity array, where each cavity interacts with an atom
under the rotating-wave approximation. For a staggered pattern of inter-cavity
couplings, a pair of field normal modes each bi-localized at the two array ends
arise. A rich structure of dynamical regimes can hence be addressed depending
on which resonance condition between the atom and field modes is set. We show
that this can be harnessed to carry out high-fidelity quantum-state transfer
(QST) of photonic, atomic or polaritonic states. Moreover, by partitioning the
array into coupled modules of smaller length, the QST time can be substantially
shortened without significantly affecting the fidelity.Comment: 12 pages, 8 figure
Fault-tolerant breathing pattern in optical lattices as a dynamical quantum memory
Proposals for quantum information processing often require the development of
new quantum tech- nologies. However, here we build quantum memory by ultracold
atoms in one-dimensional optical lattices with existing state-of-the-art
technology. Under a parabolic external field, we demonstrate that an arbitrary
initial state at an end of the optical lattices can time-evolve and revive,
with very high fidelity, at predictable discrete time intervals. Physically,
the parabolic field, can catalyze a breathing pattern. The initial state is
memorized by the pattern and can be retrieved at any of the revival time
moments. In comparison with usual time-independent memory, we call this a
dynamical memory. Furthermore, we show that the high fidelity of the quantum
state at revival time moments is fault-tolerant against the fabrication defects
and even time-dependent noise
Impartial Evaluations of the Printing Quality of Paper
Several methods for the evaluation of paper have been investigated for their desirability as means of an impartial evaluation of the printing quality of paper. The halftone plate method showed the most desired results as an impartial evaluation of both coated and uncoated papers. The printing gage was not found to be a satisfactory method of evaluation. The drawdown method is especially significant in evaluating properties which influence the printing quality but lacks a suitable numerical evaluation
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