4,917 research outputs found
The Schrodinger-like Equation for a Nonrelativistic Electron in a Photon Field of Arbitrary Intensity
The ordinary Schrodinger equation with minimal coupling for a nonrelativistic
electron interacting with a single-mode photon field is not satisfied by the
nonrelativistic limit of the exact solutions to the corresponding Dirac
equation. A Schrodinger-like equation valid for arbitrary photon intensity is
derived from the Dirac equation without the weak-field assumption. The
"eigenvalue" in the new equation is an operator in a Cartan subalgebra. An
approximation consistent with the nonrelativistic energy level derived from its
relativistic value replaces the "eigenvalue" operator by an ordinary number,
recovering the ordinary Schrodinger eigenvalue equation used in the formal
scattering formalism. The Schrodinger-like equation for the multimode case is
also presented.Comment: Tex file, 13 pages, no figur
State estimation from pair of conjugate qudits
We show that, for parallel input states, an anti-linear map with respect
to a specific basis is essentially a classical operator. We also consider the
information contained in phase-conjugate pairs , and prove
that there is more information about a quantum state encoded in phase-conjugate
pairs than in parallel pairs.Comment: 4 pages, 1 tabl
Realization of All-or-nothing-type Kochen-Specker Experiment with Single Photons
Using the spontaneous parametric down-conversion process in a type-I phase
matching BBO crystal as single photon source, we perform an all-or-nothing-type
Kochen-Specker experiment proposed by Simon \QTR{it}{et al}. [Phys. Rev. Lett.
\QTR{bf}{85}, 1783 (2000)] to verify whether noncontextual hidden variables or
quantum mechanics is right. The results strongly agree with quantum mechanics.Comment: 3 figure
Study on the triphenyl tetrazolium chloride– dehydrogenase activity (TTC-DHA) method in determination of bioactivity for treating tomato paste wastewater
A quick analysis of the sludge activity method based on triphenyltetrazolium chloride-dehydrogenase activity (TTC-DHA) was developed to change the rule and status of the biological activity of the activated sludge in tomato paste wastewater treatment. The results indicate that dehydrogenase activity (DHA) can effectively facilitate the biochemical reaction of tomato paste wastewater treatment upon analysis of the influences of various DHA and kinetic factors. The biological activity of the activated sludge by TTC-DHA was changed to become applicable to aeration and wastewater treatment operation and management.Key words: Tomato paste wastewater, TTC-DHA, bioactivity, active sludge
Alloying effect on the oxidation behavior of a ductile Al0.5Cr0.25Nb0.5Ta0.5Ti1.5 refractory high-entropy alloy
Refractory high-entropy alloys (RHEAs) are widely studied because of their promising potential for ultrahigh-temperature applications. One key challenge towards the development of RHEAs as high temperature structural materials is to concurrently achieve optimum oxidation resistance and mechanical properties. Here in this work, the effect of alloying on the oxidation behavior of ductile RHEAs was studied. Specifically, a ductile RHEA, Al0.5Cr0.25Nb0.5Ta0.5Ti1.5, was alloyed with Al and Zr aiming to improve its oxidation resistance. The two modified RHEAs, Al0.75Cr0.25Nb0.5Ta0.5Ti1.5 and Al0.5Cr0.25Nb0.5Ta0.5Ti1.5Zr0.01, indeed show enhanced oxidation resistance at 800 degrees C and 1,100 degrees C, compared with Al0.5Cr0.25Nb0.5Ta0.5Ti1.5. In addition, all three RHEAs studied here show an excellent oxidation resistance at 800 degrees C compared with other RHEAs, although there is still a large space to further improve their performance at 1,100 degrees C. Internal oxidation and even nitridation are still present after oxidation exposure, indicating further efforts are required to form protective oxide scales on the surface of ductile RHEAs. Nevertheless, the work is expected to shed some light on future directions of improving the oxidation of ductile RHEAs, via the alloying route
Comment on "Quantum key distribution without alternative measurements"
In a recent paper [A. Cabello, Phys. Rev. A 61, 052312 (2000)], a quantum key
distribution protocol based on entanglement swapping was proposed. However, in
this comment, it is shown that this protocol is insecure if Eve use a special
strategy to attack.Comment: 2 Pages, 1 Figur
Spectra of Baryons Containing Two Heavy Quarks in Potential Model
In this work, we employ the effective vertices for interaction between
diquarks (scalar or axial-vector) and gluon where the form factors are derived
in terms of the B-S equation, to obtain the potential for baryons including a
light quark and a heavy diquark. The concerned phenomenological parameters are
obtained by fitting data of mesons instead of the heavy quarkonia.
The operator ordering problem in quantum mechanics is discussed. Our numerical
results indicate that the mass splitting between and
is very small and it is consistent with the heavy quark effective
theory (HQET).Comment: 16 page
Design method and verification of a hybrid prosthetic mechanism with energy-damper clutchable device for transfemoral amputees
Dependence of the decoherence of polarization states in phase-damping channels on the frequency spectrum envelope of photons
We consider the decoherence of photons suffering in phase-damping channels.
By exploring the evolutions of single-photon polarization states and two-photon
polarization-entangled states, we find that different frequency spectrum
envelopes of photons induce different decoherence processes. A white frequency
spectrum can lead the decoherence to an ideal Markovian process. Some color
frequency spectrums can induce asymptotical decoherence, while, some other
color frequency spectrums can make coherence vanish periodically with variable
revival amplitudes. These behaviors result from the non-Markovian effects on
the decoherence process, which may give rise to a revival of coherence after
complete decoherence.Comment: 7 pages, 4 figures, new results added, replaced by accepted versio
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