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41.
Electromagnetically Induced Absorption and Transparency Spectra of Degenerate Two-Level Systems with a Strong Coupling Field in Cs Vapour 下载免费PDF全文
The electromagnetically induced absorption and electromagnetically induced transparency spectra of degenerate two-level systems with a strong coupling laser were observed. The frequency detuning and intensity effect of the coupling laser were demonstrated simultaneously. A dispersion-like spectrum can be obtained when the coupling laser is situated at blue-side detuning. The absorption inversion was realized when the coupling laser intensity is small. The coherent resonance has a linewidth much narrower than the natural linewidth of the optical transitions. 相似文献
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We report experimentally the transformation from the electromagnetically induced transparency (EIT) resonance to a dispersion-like signal and eventually to a nearly symmetric absorption resonance as coupling detuning increases in A-type three-level system in the cesium vapor cell with buffer gas at room temperature. The observed absorption resonance occupies some remarkable properties of the strong amplitude and the narrow linewidth in comparison with the case without buffer gas. The relation between linewidth of the enhanced absorption resonance and buffer gas pressure is studied. With pressure increasing, linewidth of the absorption resonance becomes narrow. The sub-natural linewidth is observed in Doppler-broadened cesium vapor cell in our experiment. The experimental results are in qualitative agreement with the numerical simulations. 相似文献
43.
The wavelength modulation indices are measured based on harmonic amplitude ratio of 4famp/6famp (4famp and 6famp are the 4- and 6-th harmonic central peak amplitudes correspondingly) with the Doppler-free selective reflection modulation spectroscopy. The experiments for the 6S1/2(F = 4) → 6P3/2(F' = 5) transition of cesium D2 line with 30-MHz linewidth were carried out. The 4f- and 6f-harmonic signals were detected with two digital lock-in amplifiers separately. The maximum error for modulation indices measurement was ±0.1 within the range of m from 3 to 6. The non-linear modulation behaviour of an external cavity diode laser induced by voltage tuning was studied with this method. The method for modulation indices measurement does not require a solid etalon as usual for measuring the wavelength modulation depth and the absorption linewidth correspondingly. 相似文献
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The signals of ultracold plasma are observed by two-photon ionization of laser-cooled atom in a caesium magneto-optical trap. A simple model has been introduced to explain the creation of plasma, and the mechanism is further investigated by changing the energy of a pulsed dye laser and the number of initial cooled atoms. 相似文献
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We present a laser frequency locking to Rydberg transition with electromagnetically induced transparency(EIT)spectra in a room-temperature cesium vapor cell. Cesium levels 6S_(1/2), 6P_(3/2), and the n D_(5/2) state, compose a cascade three-level system, where a coupling laser drives Rydberg transition, and probe laser detects the EIT signal. The error signal, obtained by demodulating the EIT signal, is used to lock the coupling laser frequency to Rydberg transition. The laser frequency fluctuation, ~0.7 MHz, is obtained after locking on, with the minimum Allan variance to be 8.9 × 10~(-11).This kind of locking method can be used to stabilize the laser frequency to the excited transition. 相似文献
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Experimental investigation of the sub-Doppler transmission spectroscopy in a thin vapour layer at room temperature 下载免费PDF全文
The sub-Doppler transmission spectrum in a thin vapour layer (about 150 μm) was observed at room temperature using the wavelength modulation technology. The absorption signal and its second-order harmonic were detected with an external-cavity diode laser. A sub-Doppler spectrum corresponding to resonant transitions of the caesium D_2 line (6S_{1/2}→6P_{3/2}) was demonstrated. The dependence of the transmission signal on the intensity of the laser was also investigated. 相似文献
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本文主要从实验上研究了封闭的简并二能级铯原子系统中的电磁感应吸收效应(EIA)。当泵浦和探测光作用于铯原子的6S1/2 F=4 à 6P3/2F′=5跃迁时,获得了EIA信号,同时研究了泵浦光的频率失谐和强度对EIA信号的影响。在6S1/2 F=4 à 6P3/2 F′=4和6S1/2 F=4 à 6P3/2 F′=3两个开放的二能级系统中也观察到了EIA信号。在6S1/2 F=3 à 6P3/2 F′=4的跃迁上增加一个repumping 激光,将使EIA信号增加。 相似文献