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21.
Nanofibers have many promising applications because of their advantages of high power density and ultralow saturated light intensity. We present here a Zeeman shift of the Doppler-broadened cesium D2 transition using a tapered optical nanofiber in the presence of a magnetic field. When a weak magnetic field is parallel to the propagating light in the nanofiber, the Zeeman shift rates for different circularly polarized spectra are observed.For the +component, the typical linear Zeeman shift rates of = 3 and = 4 ground-state cesium atoms are measured to be 3.10(±0.19) MHz/G and 3.91(±0.16) MHz/G. For the -component, the values are measured to be-2.81(±0.25) MHz/G, and-0.78(±0.28) MHz/G. The Zeeman shift using the tapered nanofiber can help to develop magnetometers to measure the magnetic field at the narrow local region and the dispersive signal to lock laser frequency. 相似文献
22.
Experimental Study on Double Resonance Optical Pumping Spectroscopy in a Ladder-Type System of ~(87)Rb Atoms 下载免费PDF全文
Double resonance optical pumping spectroscopy has an outstanding advantage of high signal-to-noise ratio, thus having potential applications in precision measurement. With the counter propagated 780 nm and 776 nm laser beams acting on a rubidium vapor cell, the high resolution spectrum of 5S_(1/2)-5P_(3/2)-5D_(5/2) ladder-type transition of ~(87)Rb atoms is obtained by monitoring the population of the 5S_(1/2) ground state. The dependence of the spectroscopy lineshape on the probe and coupling fields are comprehensively studied in theory and experiment.This research is helpful for measurement of fundamental physical constants by high resolution spectroscopy. 相似文献
23.
噪声免疫腔增强光外差分子光谱技术(NICE-OHMS)由于结合了频率调制光谱与腔增强光谱两种技术,不仅可以将激光耦合到高精细度谐振腔大幅提高腔内功率,还可以实现低气压样品气体的高灵敏测量,因此基于该技术可以实现分子吸收线的饱和,获得亚多普勒光谱,从而能作为激光频率锁定的参考.本文基于光纤激光器的NICE-OHMS技术,将光纤激光器频率锁定到NH3的亚多普勒吸收线上.首先分析了基于Pound-Drever-Hall和DeVoe-Brewer技术实现激光到腔模和调制频率到腔自由光谱区频率锁定的性能,之后在腔内气压为70 mTorr条件下,测量了半高全宽为2.05 MHz的NH3亚多普勒信号,最后将1.53μm的光纤激光器频率锁定到该亚多普勒吸收线上,相对频率偏差为16.3 kHz,阿伦方差结果显示,136 s积分时间下频率稳定度达到1.6×10~(-12). 相似文献
24.
Photoassociation spectra of ultracold ~(85)Rb_2 molecule in 0_u~+ long range state near the 5S_(1/2)+ 5P_(1/2) asymptote 下载免费PDF全文
We investigate the high resolution photoassociation spectra of ~(85)Rb_2 molecules in 0~+_u long range state below the(5S_(1/2)+ 5P_(1/2)) asymptote. The ~(85)Rb atomic samples are trapped in a dark magneto–optical trap(MOT) and prepared in the dark state. With the help of trap loss technique, we obtain considerable photoassociation spectroscopy with rovibrational resolution, some of which have never been observed before. The observed spectrum is fitted by a rigid rotation model, and the rotational constants of ultracold ~(85)Rb_2 molecule in long range 0~+_u are obtained for different vibrational states. By applying the Le Roy–Bernstein method, we assign the vibrational quantum numbers and derive C_3 coefficient, which is used to obtain the potential energy curve. 相似文献
25.
Systematically investigating the polarization gradient cooling in an optical molasses of ultracold cesium atoms 下载免费PDF全文
We systematically investigate the polarization gradient cooling (PGC) process in an optical molasses of ultracold cesium atoms. The SR mode for changing the cooling laser, which means that the cooling laser frequency is stepped to the setting value while its intensity is ramped, is found to be the best for the PGC, compared with other modes studied. We verify that the heating effect of the cold atoms, which appears when the cooling laser intensity is lower than the saturation intensity, arises from insufficient polarization gradient cooling. Finally, an exponential decay function with a statistical explanation is introduced to explain the dependence of the cold atom temperature on the PGC interaction time. 相似文献
26.
27.
Direct measurement of the surface dynamics of supercooled liquid-glycerol by optical scanning a film 下载免费PDF全文
The surface dynamics of supercooled liquid-glycerol is studied by
scanning the thickness of the glycerol film with single photon
detection. Measurements are performed at room temperature well above
the glycerol's glass transition temperature. It is shown that the
surface dynamics of the glycerol film is very sensitive to the
temperature. The linear relationship between the thickness of the
film and the viscosity predicted by the Vogel--Fulcher--Tammann--Hesse
(VFTH) law is also presented experimentally. 相似文献
28.
Electromagnetically-induced transparency is observed in a three-level multi-V-type system in cesium vapour at room temperature.The absorption property is measured and the hyperfine structures of atomic states can be datermined.The results of the experiment agree with the theoretical analysis. 相似文献
29.
30.
In this paper the generation of four-wave mixing (FWM) signal using a
noncycling transition of caesium atoms is investigated when the pumping laser
is locked to the transition $6{\rm S}_{1/2}F=4\to6{\rm P}_{3/2}F'=4$, and
meanwhile the probe frequency is scanned across the $6{\rm S}_{1/2}F=4
\to6{\rm P}_{3/2}$ transition. The efficiency of the four-wave mixing signal
as a function of the intensity of the pumping beams and the detuning of the
pumping beams is also studied. In order to increase the detection
efficiency, a repumping laser which is resonant with $6{\rm S}_{1/2}
F=3\to 6{\rm P}_{3/2}F'=4$ transition is used. A theoretical model is also
introduced, and the theoretical results are in qualitative agreement with
experimental ones. 相似文献