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Microscopic mechanism of plasmon-mediated photocatalytic H2 splitting on Ag–Au alloy chain 下载免费PDF全文
Alloy nanostructures supporting localized surface plasmon resonances has been widely used as efficient photocatalysts, but the microscopic mechanism of alloy compositions enhancing the catalytic efficiency is still unclear. By using time-dependent density functional theory(TDDFT), we analyze the real-time reaction processes of plasmon-mediated H2 splitting on linear Ag–Au alloy chains when exposed to femtosecond laser pulses. It is found that H2 splitting rate depends on th... 相似文献
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实现了将预冷却(温度约为1~2μK)的87 Rb和40 K原子装载到远红失谐的光学偶极力阱中,继而利用逐步降低光强的方法对其进行蒸发冷却,获得了87 Rb原子的玻色-爱因斯坦凝聚(BEC),并用协同冷却的方法得到了40 K原子的量子简并(DFG)。实验上通过光纤传输远红失谐激光束降低了光束指向性的抖动,又利用光强反馈伺服系统抑制远红失谐激光的强度抖动,提高了获得玻色-爱因斯坦凝聚和简并费米气体的重复性和稳定性。实验上得到玻色-爱因斯坦凝聚的原子数达8.48×105个,简并费米气体的原子数量约为3.34×106个。 相似文献
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Radio-frequency spectroscopy of weakly bound molecules in ultracold Fermi gasRadio-frequency spectroscopy of weakly bound molecules in ultracold Fermi gasRadio-frequency spectroscopy of weakly bound molecules in ultracold Fermi gas 下载免费PDF全文
We create weakly bound Feshbach molecules in ultracold Fermi gas 4~K by sweeping a magnetic field across a broad Feshbach resonance point 202.2 G with a rate of 20 ms/G and perform the dissociation process using radio-frequency (RF) technology. From RF spectroscopy, we obtain the binding energy of the weakly bound molecules in the vicinity of Feshbach resonance. Our measurement also shows that the number of atoms generated from the dissociation process is different at various magnetic fields with the same RF amplitude, which gives us a deeper understanding of weakly bound Feshbach molecules. 相似文献
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Experimental investigation of evaporative cooling mixture of bosonic 87Rb and fermionic 40K atoms with microwave and radio frequency radiation 下载免费PDF全文
We investigate sympathetic cooling fermions 40K by evaporatively cooling bosonic 87Rb atoms in a magnetic trap with microwave and radio frequency induced evaporations in detail. The mixture of bosonic and fermionic atoms is prepared in their polarized spin states |F=9/2, mF=9/2> for 40K and |F=2, mF=2> for 87Rb, which is trapped in Quadrupole--Ioffe--Configuration trap. Comparing microwave with radio frequency evaporatively cooling bosonic 87Rb atoms with sympathetically cooling Fermi gas 40K, we find that the presence of rubidium atoms in the |2,1> Zeeman states, which are generated in the evaporative process, gives rise to a significant loss of 40K due to inelastic collisions. Thus, the rubidium atoms populated in the |2, 1> Zeeman states should be removed in order to effectively perform sympathetically cooling 40K with the evaporatively cooled 87Rb atoms. 相似文献
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We report the experimental preparations of the absolute ground states of 87Rb and 40K atoms (| F=1, mF=1,〉+ |F=9/2, mF=-9/2,〉) by means of the radio-frequency and microwave adiabatic rapid passages, and the observation of magnetic Feshbach resonances in an ultracold mixture of bosonic 87Rb and fermionic 40K atoms between 0 T and 6.0 × 10-2 T, including 7 homonuclear and 4 heteronuclear Feshbach resonances. The resonances are identified by the abrupt trap loss of atoms induced by the strong inelastic three-body collisions. These Feshbach resonances should enable the experimental control of interspecies interactions. 相似文献
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We create a Bose-Einstein condensate(BEC) of 87Rb atoms by runaway evaporative cooling in an optical trap.Two crossed infrared laser beams with a wavelength of 1064 nm are used to form an optical dipole trap.After precooling the atom samples in a quadrupole-Ioffe configuration(QUIC) trap under 1.5 μK by radio-frequency(RF) evaporative cooling,the samples are transferred into the center of the glass cell,then loaded into the optical dipole trap with 800 ms.The pure condensate with up to 1.5×105 atoms is obtained over 1.17 s by lowering the power of the trap beams. 相似文献
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We create weakly bound Feshbach molecules in ultracold Fermi gas40K by sweeping a magnetic field across a broad Feshbach resonance point 202.2 G with a rate of 20 ms/G and perform the dissociation process using radio-frequency(RF) technology. From RF spectroscopy, we obtain the binding energy of the weakly bound molecules in the vicinity of Feshbach resonance. Our measurement also shows that the number of atoms generated from the dissociation process is different at various magnetic fields with the same RF amplitude, which gives us a deeper understanding of weakly bound Feshbach molecules. 相似文献
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