c-axis optical conductivity from the Yang-Rice-Zhang model of the underdoped cuprates

The c-axis optical response of the underdoped cuprates is qualitatively different from its in-plane counterpart. The features of the pseudogap show themselves more prominently in the c-axis than in-plane. We compute both the c-axis optical conductivity and the in-plane optical conductivity using the Yang-Rice-Zhang model of underdoped cuprates. This model combined with coherent interlayer tunneling is enough to explain the qualitative differences between the in-plane data and the c-axis data. We show how pseudogap features manifest themselves in the infrared and microwave conductivity within this model.