We study non-linear absorption of intense monochromatic light through a dense natural rubidium (Rb) vapour. We measure transmission through a 10 cm long heated vapour cell for atom densities up to 3 × 10 19 m −3 and saturation parameters up to 10 4 , for linear and circular polarisation, close to resonance on the 87 Rb D 2 F = 1 → F ′ = 0, 1, 2 transition. The strong absorption at low intensity is frustrated by an interplay of optical non-linearities (saturation and optical pumping) and non-linear effects due to the high atom density (collisional broadening and collisional depumping). To understand the results of the transmission measurements, we developed a model that incorporates these non-linear effects into the optical absorption. The model takes into account the absolute line strengths of all transitions from both hyperfine levels of the ground state of both isotopes of naturally abundant Rb. Doppler and collisio...

中文翻译：

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非线性光学和碰撞过程对浓dense蒸气中吸收饱和度的综合影响

我们研究通过密集的天然rub（Rb）蒸气对强烈单色光的非线性吸收。我们测量通过10厘米长的加热蒸气池的传输，原子密度高达3×10 19 m -3，饱和参数高达10 4，对于线性和圆极化，接近于87 Rb D 2 F = 1→的共振F'= 0、1、2过渡。光学非线性（饱和度和光泵浦）和非线性效应（高原子密度（碰撞加宽和碰撞去泵浦））的相互作用会阻碍低强度下的强吸收。为了了解透射测量的结果，我们开发了一个模型，将这些非线性效应纳入光吸收。该模型考虑了自然丰富的Rb的两个同位素的基态的两个超精细水平的所有跃迁的绝对谱线强度。多普勒和大肠镜