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With a combined analysis of data on Υ(5S)→hb(1P,2P)π+π- and Υ(5S)→B(∗)B¯(∗)π in an effective field theory approach, we determine resonance parameters of Zb states in two scenarios. In one scenario we assume that Zb states are pure molecular states, while in the other one we assume that Zb states contain compact components. We find that the present data favor that there should be some compact components inside Zb(′) associated with the molecular components. By fitting the invariant mass spectra of Υ(5S)→hb(1P,2P)π+π- and Υ(5S)→B(∗)B¯∗π , we determine that the probability of finding the compact components in Zb states may be as large as about 40 %.

Using the optical guided wave method,the full leaky waveguide mode assembled by prism,matching fluid of refractivity and twisted nematic liquid crystal cell is studied under different voltages.Some experimental data of reflected light corresponding to different external angles through the full leaky guided mode of twisted nematic liquid crystal are obtained.From Snell law,some experimental curves between the reflectivity and the internal angle are also obtained.By comparing these experimental curves with the theoretical curves obtained from multi-layer optics theory,with a greatly good accordance,the director profile of twisted nematic liquid crystal cell for different voltages is determined.

With a combined analysis of data on $��(5S)\rightarrow h_b(1P,2P)��^+��^-$ and $��(5S)\rightarrow B^{(\ast)}\bar B^{(\ast)}��$ in an effective field theory approach, we determine resonance parameters of $Z_b$ states in two scenarios. In one scenario we assume that $Z_b$ states are pure molecular states, while in the other one we assume that $Z_b$ states contain compact components. We find that the present data favor that there should be some compact components inside $Z_b^{(\prime)}$ associated with the molecular components. By fitting the invariant mass spectra of $��(5S)\rightarrow h_b(1P,2P)��^+��^-$ and $��(5S)\rightarrow B^{(\ast)}\bar B^{\ast}��$, we determine that the probability of finding the compact components in $Z_b$ states may be as large as about $40\%$., Discussions added, version published in EPJC

We study the anomalous cross-section lineshape of $e^+e^-\rightarrow D\bar D$ with an effective field theory. Near the threshold, most of the $D\bar D$ pairs are from the decay of $��(3770)$. Taking into account the fact that the nonresonance background is dominated by the $��(2S)$ transition, the produced $D\bar D$ pair can undergo final-state interactions before the pair is detected. We propose an effective field theory for the low-energy $D\bar D$ interactions to describe these final-state interactions and find that the anomalous lineshape of the $D\bar D$ cross section observed by the BESII collaboration can be well described., 10 pages,6 figures, redo the calculation with PDS scheme and more discussions added, accepted by Phys.Lett.B

The eigenvalue equation of the step finite strained single quantum well is deduced from Schrdinger equation, the influence of the step width on first electron energy, first hole energy, the stimulated wavelength, and the influence of the first hole energy on stimulated wavelength are studied. The results indicate that, if the In content is large, the influence of the first hole energy on the stimulated wavelength should not be neglected. The calculated value by using this model is in accord with the experiment results.

Based on physics of micro-cavity and quantum well, the spontaneous emission spectra and spontaneous emission lifetime in the vertical cavity surface emitting laser have been calculated. It is found that the minimum spontaneous emission lifetime is the main reason that the vertical cavity surface emitting laser can realize high\|modulation response after the transfer function of the semiconductor laser is studied.

We study the anomalous cross-section lineshape of e+e−→DD¯ with an effective field theory. Near the threshold, most of the DD¯ pairs are from the decay of ψ(3770). Taking into account the fact that the nonresonance background is dominated by the ψ(2S) transition, the produced DD¯ pair can undergo final-state interactions before the pair is detected. We propose an effective field theory for the low-energy DD¯ interactions to describe these final-state interactions and find that the anomalous lineshape of the DD¯ cross section observed by the BESII Collaboration can be well described.