c-axis response of a high-Tc superconductor with d-density-wave order -: art. no. 064502

The microscopic origin of the pseudogap state that exists in the underdoped cuprates remains unknown. The c-axis properties in the pseudogap regime are particularly anomalous, We use a recently proposed model of a d density wave that leads to staggered currents and the doubling of the unit cell to investigate the c-axis kinetic energy and the optical sum rule. The density of states expected in the model is also considered.