Next Article in Journal
First-Principles Study of the Impact of Grain Boundary Formation in the Cathode Material LiFePO4
Previous Article in Journal
Review: Interactions of Active Colloids with Passive Tracers
Open AccessArticle

Theory of Time-Resolved Optical Conductivity of Superconductors: Comparing Two Methods for Its Evaluation

Department of Physics, North Carolina State University, Raleigh, NC 26695, USA
*
Author to whom correspondence should be addressed.
Condens. Matter 2019, 4(3), 79; https://doi.org/10.3390/condmat4030079
Received: 4 July 2019 / Revised: 22 August 2019 / Accepted: 22 August 2019 / Published: 27 August 2019
Time-resolved optical conductivity is an often used tool to interrogate quantum materials driven out of equilibrium. Theoretically calculating this observable is a complex topic with several approaches discussed in the literature. Using a nonequilibrium Keldysh formalism and a functional derivative approach to the conductivity, we present a comparison of two particular approaches to the calculation of the optical conductivity and their distinguishing features, as applied to a pumped superconductor. The two methods are distinguished by the relative motion of the probe and gate times; either the probe or gate time is kept fixed while the other is swept. We find that both the methods result in same qualitative features of the time-resolved conductivity after pump is over. However, calculating the conductivity by keeping the gate fixed removes artifacts inherent to the other method. We provide software that, based on data for the first method, is able to construct the second approach. View Full-Text
Keywords: pump–probe experiments; time-resolved optical conductivity; Higgs oscillations pump–probe experiments; time-resolved optical conductivity; Higgs oscillations
Show Figures

Figure 1

MDPI and ACS Style

Revelle, J.P.; Kumar, A.; Kemper, A.F. Theory of Time-Resolved Optical Conductivity of Superconductors: Comparing Two Methods for Its Evaluation. Condens. Matter 2019, 4, 79.

Show more citation formats Show less citations formats
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Back to TopTop