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Temperature of the Remaining Cold Atoms after Two-Step Photoionization in an ^87Rb Vapor Cell Magneto-Optical Trap 下载免费PDF全文
The temperature of the remaining cold ^87Rb atoms confined in a vapor cell magneto-optical trap after two-step photoionization has been measured. In the two-step photoionization process, the first excitation laser is served by the cooling laser and the second excitation laser is served by a continuous semiconductor laser with a wavelength of 450hm. The results show that the temperature of the remaining cold atoms decreases as the intensity of the second excitation laser increases. Moreover, the relationship between the temperature T and number N of the remaining cold atoms generally foliows a power law, while it deviates from the well-known T ∝ N^1/3 and the power factor is smaller than 1/3. We propose that ion-atom collisions occurring during a photoionization process strongly influence the temperature sealing law in an optiealiy dense magneto-optical trap in the presence of an ionization laser. In addition, the forced evaporative cooling due to the combined effect of the detuning of the first excitation laser and the two-step photoionization plays a role in cooling the remaining cold atoms and results in the dependence of the power factor on the detuning of the first excitation laser. 相似文献
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证明了双诱导映射下L-Fuzzy子格群的像与逆像仍为L-Fuzzy子格群,基于L-Fuzzy集的层次结构特征,研究L-Fuzzy子格群的同态,给出了它们的性质. 相似文献
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本文得到了从Fibonacci数列{F_n}~∞_n=1中(有放回)随机取m(≥2)项其最大公因子为F_(no≥3)的概率;讨论了Mersenne数列{2~n-1}~∞_n=1的概率性质,并发现它与Fibonacci数列的概率性质相似. 相似文献
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给出了生成L-Fuzzy子群的代数刻画式.基于L-Fuzzy集上的双诱导映射理论和层次结构特征,研究了生成L-Fuzzy子群的若干性质,得到内积的生成L-Fuzzy子群等于生成L-Fuzzy子群的内积,L-Fuzzy正规子群的并的生成L-Fuzzy子群仍是L-Fuzzy正规子群,L-Fuzzy子集的同态映像的生成L-Fuzzy子群等于L-Fuzzy子集的生成L-Fuzzy子群的同态映像等一系列颇有意义的结论. 相似文献
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再论微分中值定理“中间点”ξ的性质 总被引:1,自引:0,他引:1
主要研究拉格朗日中值定理"中间点"ξ的单调性、连续性及可导性问题. 相似文献
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