When decay rate in the coupling channel is greater than that in the probe channel, the incoherent population pumping in the probe channel can create the gain without inversion.

当耦合路径上的衰变率大于探测路径上的衰变率时，探测路径上的抽运导致了非逆转增益现象的产生。

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Using rate equation theory, the equation group including the population inversion density of the gain medium, photon density and the absorber ground state population density is acquired.

利用速率方程理论，得到包含激光增益介质反转密度、光子密度和饱和吸收介质基态布居数密度的速率方程组。

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Orders for goods expected to last at least three years fell 1% last month, an inversion of the 1% gain that economists had expected.

FORBES