We have examined the use of alkali metal (rubidium) vapour for spectral filtering of broadband pulsed laser light that is used to produce a femtosecond pulsed optical dipole trap. It has been shown that, even at large detuning of the centre emission frequency from the frequency of atomic transitions, spectral components present in the wings of the laser emission line are capable of heating localised atoms, thus reducing their lifetime in the atomic trap. Using atomic vapour for filtering the laser emission spectrum, we have suppressed its spectral components resulting in heating. This has made it possible to increase the lifetime of atoms in the pulsed optical dipole trap to a value comparable to their lifetime in an optical trap formed by narrow-band cw laser light.

中文翻译：

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具有激光辐射光谱滤波的原子偶极脉冲阱

我们研究了使用碱金属（铷）蒸气对宽带脉冲激光进行光谱过滤，该激光用于产生飞秒脉冲光偶极子陷阱。已经表明，即使中心发射频率与原子跃迁频率有很大的失谐，激光发射线翼中存在的光谱分量也能够加热局部原子，从而缩短它们在原子陷阱中的寿命。使用原子蒸气过滤激光发射光谱，我们抑制了导致加热的光谱成分。这使得将脉冲光偶极子陷阱中原子的寿命增加到与它们在由窄带连续激光形成的光陷阱中的寿命相当的值成为可能。