Nodal quasiparticle lifetimes in cuprate superconductors

Abstract

A new generation of angular-resolved photoemission spectroscopy (ARPES) measurements on the cuprate superconductors offer the promise of enhanced momentum and energy resolution. In particular, the energy and temperature dependence of the on-shell nodal (kx = ky) quasiparticle scattering rate can be studied. In the superconducting state, low temperature transport measurements suggest that one can describe nodal quasiparticles within the framework of a BCS d-wave model by including forward elastic scattering and spin-fluctuation inelastic scattering. Here, using this model, we calculate the temperature and frequency dependence of the on-shell nodal quasiparticle scattering rate in the superconducting state which determines the momentum width of the ARPES momentum distribution curves. For a zero-energy quasiparticle at the nodal momentum kN , both the elastic and inelastic scattering rate show a sudden decrease as the temperature drops below Tc, reflecting the onset of the gap amplitude. At low temperatures the scattering rate decreases as T 3 and approaches a zero temperature value determined by the elastic impurity scattering. For T > Tc, we find a quasilinear dependence on T . At low reduced temperatures, the elastic scattering rate for the nodal quasiparticles exhibits a quasilinear increase at low energy ω which arises from elastic scattering processes. The inelastic spin-fluctuation scattering leads to a low energy ω 3 dependence which, for ω 3∆0, crosses over to a quasilinear behavior.

Nodal quasiparticle dynamics in the heavy fermion superconductor CeCoIn5 revealed by precision microwave spectroscopy

“…The prefactor A is expected to be of order one 48 : numerical spinfluctuation calculations obtain A ¼ 2.4 for parameters relevant to optimally doped cuprates 50 ; fits to our CeCoIn 5 data give A ¼ 3.36. With these values so close, the charge dynamics of CeCoIn 5 seem to be consistent with a spin-fluctuation mechanism.…”

“…In a d-wave superconductor, both regimes are expected to carry signatures of the nodal quasiparticle spectrum, namely, the linear energy dependence of the density of states [47][48][49][50] .…”

Fine details of the nodal electronic excitations inBi2Sr2CaCu2O8+Valla1, Kidd2, Rameau3 et al. 2006Phys. Rev. B248170View full textAdd to dashboardCite

“…In particular, one of our earlier studies reported that the spectral width in the nodal region was almost completely insensitive to the superconducting transition [3]. Theoretical studies indicate that in the superconducting state, phase space restrictions should result in a cubic dependence on T and ω [15].In the present letter, we focus on these issues again and show that the sample quality and experimental resolution are crucial factors in resolving "fine details" of the electronic structure near the nodal point. We show…”

Quasi-particle interference probe of the self-energy

“…We have set (k, ω) = (1 − Z (k, ω))ω and E(k) is the bandstructure energy minus the chemical potential µ. For illustration, we will calculate Z (k, ω) = Z 1 (k, ω) + iZ 2 (k, ω) for a Hubbard model using a random phase approximation (RPA) for the spin-fluctuation interaction [19] (…”