本文求解了描述负折射介质中超短脉冲传输的归一化薛定谔方程，发现负折射介质中可以存在一种非线性啁啾暗孤波。结合负折射介质的特性，详细研究了该啁啾暗孤波的形成条件和传输特性。结果发现，与普通介质中的暗孤波不同，该啁啾暗孤波只能存在于介质的反常色散区，且孤波的速度影响其啁啾和幅度。另外，我们数值研究了该啁啾暗孤波在诸如频率偏移、功率波动和噪声干扰下的稳定性，结果表明，这种啁啾暗孤波在有限的扰动下具有很好的稳定性。

In this paper, we study the generalized Schrdinger equation describing the propagation of ultrashort pulses in nonlinear negative index materials and find that there exists a new dark solitary wave solution with nonlinear chirp. Based on the characteristics of nonlinear negative index materials, we investigate the formation conditions and transmission characteristics of the chirped dark solitary wave in detail. The obtained results demonstrate that the chirped dark solitary wave, which is distinctly different from dark solitons in ordinary medium, can only exist in anomalous dispersion region of negative index materials. Also, the velocity of this dark solitary wave affects its chirp and amplitude are related to its velocity. Further, we numerically discuss the stability of the chirped dark solitary wave under the perturbations such as frequency deviation, fluctuation of power and random noise. The numerical results show that the chirped dark solitary wave is quite stable under the limited perturbations.