Charge order in the cuprates
Andrey V. Chubukov,
University of Minnesota
I analyze
charge order in hole-doped cuprates. I argue that
magnetically-mediated interaction, which is known to give rise to
d-wave superconductivity, also gives rise to charge-density-wave
instabilities with momenta Qx =(Q,0) and Qy
=(0,Q), as seen in the experiments. I show that the emerging charge
order with Qx/Qy is of stripe type and that a stripe CDW order
parameter by itself has two components: one is incommensurate density
variation, another is incommensurate current. Both components are
non-zero in the CDW-ordered state, with the relative phase
±π/2. Such an order breaks time reversal and mirror
symmetries and give rise to a non-zero Kerr effect. I further show
that, before a true incommensurate CDW order sets in, the system
develops a pre-emptive composite order which breaks lattice rotational
symmetry and time-reversal symmetry but preserves a translational U(1)
symmetry. I discuss the interplay between our CDW order and pair
density-wave order (superconducting order with a finite total momentum
of a pair) and present the phase diagram of underdoped cuprates.