Non-equilibrium Pair Breaking in Ba(Fe1-xCox)2As2 Superconductors: Evidence for Formation of Photo-Induced Excitonic Spin-Density-Wave State

Abstract

Ultrafast terahertz (THz) pump{probe spectroscopy reveals unusual out-of-equilibrium Cooper pair dynamics driven by femtosecond (fs) optical quench of superconductivity (SC) in iron pnictides. We observe a two{step quench of the SC gap, where an abnormally slow (many 100's of ps) quench process is clearly distinguished from the usual fast (sub-ps) hot{phonon{mediated scattering channel. This pair breaking dynamics depends strongly on doping, pump uence, and temperature. The above observations, together with quantum kinetic modeling of non-equilibrium SC and magnetic correlations, provide evidence for photogeneration of a transient state where SC competes with build{up of spin-density-wave (SDW) excitonic correlation between quasi-particles (QP).

arXiv commentmain text + supplementary

References in corpus (18)

• Ultrafast optical spectroscopy of strongly correlated materials and high-temperature superconductors: a non-equilibrium approach
• FeAs-based superconductivity: a case study of the effects of transition metal doping on BaFe2As2
• Non-thermal separation of electronic and structural orders in a persisting charge density wave
• Competing order and nature of the pairing state in the iron pnictides
• Broadband terahertz generation from metamaterials
• Ultrafast transient generation of spin-densitywave order in the normal state of BaFe2As2 driven by coherent lattice vibrations
• Kinetics of a superconductor excited with a femtosecond optical pulse
• Superconductivity and spin-density-waves in multi-band metals
• Pair-breaking and superconducting state recovery dynamics in MgB2
• Energy-gap dynamics of superconducting NbN thin films studied by time-resolved terahertz spectroscopy
• Electrodynamics of electron doped iron-pnictide superconductors: Normal state properties
• Ultrafast observation of critical nematic fluctuations and giant magnetoelastic coupling in iron pnictides
• Spin excitations in the excitonic spin-density-wave state of the iron pnictides
• Ultrafast terahertz probes of interacting dark excitons in chirality-specific semiconducting single-walled carbon nanotubes
• Theory of nonequilibrium dynamics of multiband superconductors
• Reversible modulation and ultrafast dynamics of THz resonances in strongly photoexcited metamaterials
• Correlating Quasi-Electron Relaxation with Quantum Femtosecond Magnetism in the Order Parameter Dynamics of Insulating Manganites
• Pair-excitation energetics of highly correlated many-body states

Cited by in corpus (14)

• Ultrafast Terahertz Conductivity Probes of Topologically Enhanced Surface Transport Driven by Mid-Infrared Laser Pulses in Bi${}_2$Se${}_3$
• Light-Driven Raman Coherence as a Non-Thermal Route to Ultrafast Topology Switching
• Discovery of Terahertz Second Harmonic Generation from Lightwave Acceleration of Symmetry--Breaking Nonlinear Supercurrents
• Quantum Coherence Tomography of Lightwave Controlled Superconductivity
• Light Quantum Control of Persisting Higgs Modes in Iron-Based Superconductors
• Ultrafast Control of Excitonic Rashba Fine Structure by Phonon Coherences in a Metal Halide Perovskite CH${}_3$NH${}_3$PbI${}_3$
• Competing Orders and Ultrafast Energy Transfer at the Quantum Limit in a Nb${}_3$Sn Superconductor Probed by Terahertz Electrodynamics
• Coherent Band-Edge Oscillations and Dynamic LO Phonon Mode Splitting as Evidence for Polaronic Coupling in Perovskites
• Lightwave Terahertz Quantum Manipulation of Non-equilibrium Superconductor Phases and their Collective Modes
• Impact of damping on superconducting gap oscillations induced by intense Terahertz pulses
• Higgs Oscillations in time-resolved Optical Conductivity
• HHG-laser-based time- and angle-resolved photoemission spectroscopy of quantum materials
• Visualizing heterogeneous dipole fields by terahertz light coupling in individual nano-junctions used in transmon qubits
• Multi-Dimensional Coherent Spectroscopy of Light-Driven States and their Collective Modes in Multi-Band Superconductors