Theory of driven Higgs oscillations and third-harmonic generation in unconventional superconductors

Abstract

Higgs spectroscopy is a new field in which Higgs modes in nonequilibrium superconductors are analyzed to gain information about the ground state. One experimental setup in which the Higgs mode in s-wave superconductors was observed is periodic driving with THz light, which shows resonances in the third-harmonic generation (THG) signal if twice the driving frequency matches the energy of the Higgs mode. We derive expressions of the driven gap oscillations for arbitrary gap symmetry and calculate the THG response. We demonstrate that the possible Higgs modes for superconductors with non-trivial gap symmetry can lead to additional resonances if twice the driving frequency matches the energy of these Higgs modes and we disentangle the influence of charge density fluctuations (CDF) to the THG signal within our clean-limit analysis. With this we show that THG experiments on unconventional superconductors allow for a detection of their Higgs modes. This paves the way for future studies on realistic systems including additional features to understand the collective excitation spectra of unconventional superconductors.

arXiv comment16 pages, 8 figures, updated and extended

References in corpus (43)

• An optically stimulated superconducting-like phase in K3C60 far above equilibrium Tc
• Ultrafast optical spectroscopy of strongly correlated materials and high-temperature superconductors: a non-equilibrium approach
• Higgs Amplitude Mode in BCS Superconductors Nb${}_{1-x}$Ti${}_x$N induced by Terahertz Pulse Excitation
• Amplitude / Higgs Modes in Condensed Matter Physics
• Optically induced coherent transport far above Tc in underdoped YBa2Cu3O6+x
• Solitons and Rabi Oscillations in a Time-Dependent BCS Pairing Problem
• Nonlinear light-matter interaction at terahertz frequencies
• Synchronization in the BCS Pairing Dynamics as a Critical Phenomenon
• Visibility of the Amplitude (Higgs) Mode in Condensed Matter
• Theory of Anderson pseudospin resonance with Higgs mode in superconductors
• Amplitude `Higgs' mode in 2H-NbSe2 Superconductor
• Dynamical vanishing of the order parameter in a fermionic condensate
• Non-linear optical effects and third-harmonic generation in superconductors: Cooper-pairs vs Higgs mode contribution
• Phase-resolved Higgs response in superconducting cuprates
• Higgs mode in the d-wave superconductor Bi2Sr2CaCu2O8+x driven by an intense terahertz pulse
• Coupling of Higgs and Leggett modes in nonequilibrium superconductors
• Polarization-resolved terahertz third-harmonic generation in a superconductor NbN: dominance of Higgs mode beyond the BCS approximation
• Direct observation of Higgs mode oscillations in the pump-probe photoemission spectra of electron-phonon mediated superconductors
• Amplitude Higgs mode and admittance in superconductors with a moving condensate
• Nonlinear electromagnetic response and Higgs mode excitation in BCS superconductors with impurities
• Classification and characterization of nonequilibrium Higgs modes in unconventional superconductors
• Pressure induced collapse of the charge density wave and Higgs mode visibility in 2H-TaS${}_2$
• Transient Dynamics of d-wave Superconductors after a Sudden Excitation
• Nonlinear optical response of collective modes in multiband superconductors assisted by nonmagnetic impurities
• Infrared activation of the Higgs mode by supercurrent injection in superconducting NbN
• Signatures of nonadiabatic BCS state dynamics in pump-probe conductivity
• Higgs-mode radiance and charge-density-wave order in 2H-NbSe${}_2$
• Theory of light-induced resonances with collective Higgs and Leggett modes in multiband superconductors
• Twisting Anderson pseudospins with light: Quench dynamics in THz-pumped BCS superconductors
• Nonlinear light-Higgs coupling in superconductors beyond BCS: Effects of the retarded phonon-mediated interaction
• Higgs-mediated optical amplification in a non-equilibrium superconductor
• Polarization dependence of the third-harmonic generation in multiband superconductors
• Multiple amplitude modes in strongly-coupled phonon-mediated superconductors
• Detecting superconductivity out-of-equilibrium
• Resonant generation of coherent phonons in a superconductor by ultrafast optical pump pulses
• Quasiclassical Theory on Third-Harmonic Generation in Conventional Superconductors with Paramagnetic Impurities
• Theory for ultrafast nonequilibrium dynamics in d-wave superconductors
• Electronic and phononic Raman scattering in detwinned YBa${}_2$Cu${}_3$O${}_{6.95}$ and Y${}_{0.85}$Ca${}_{0.15}$Ba${}_2$Cu${}_3$O${}_{6.95}$: s-wave admixture to the $d_{x^2-y^2}$-wave order parameter
• Theory of nonequilibrium dynamics of multiband superconductors
• Possible light-induced superconductivity in a strongly correlated electron system
• Amplitude mode oscillations in pump-probe photoemission spectra from a d-wave superconductor
• Two-Photon Absorption by Impurity Scattering and Amplitude Mode in Conventional Superconductors
• Screening in (d+s)-wave superconductors: Application to Raman scattering

Cited by in corpus (24)

• Phase-resolved Higgs response in superconducting cuprates
• Higgs-mode resonance in third harmonic generation in NbN superconductors: multiband electron-phonon coupling, impurity scattering, and polarization-angle dependence
• Spectroscopic signatures of time-reversal symmetry breaking superconductivity
• Band-selective third-harmonic generation in superconducting MgB${}_2$: Possible evidence for Higgs amplitude mode in the dirty limit
• High-order nonlinear terahertz probing of the two-band superconductor MgB${}_2$: Third- and fifth-order harmonic generation
• Transient Higgs oscillations and high-order nonlinear light-Higgs coupling in terahertz-wave drivenNbN superconductor
• Following the Higgs mode across the BCS-BEC crossover in two dimensions
• Contribution of Collective Excitations to Third Harmonic Generation in Multiband Superconductors: the case of MgB${}_2$
• Observation of terahertz second harmonic generation from Dirac surface states in the topological insulator Bi${}_2$Se${}_3$
• Phase signatures in third-harmonic response of Higgs and coexisting modes in superconductors
• Quench-drive spectroscopy and high-harmonic generation in BCS superconductors
• Higgs-like pair amplitude dynamics in superconductor-quantum dot hybrids
• Calculation of an enhanced A1g symmetry mode induced by Higgs oscillations in the Raman spectrum of high-temperature cuprate superconductors
• Floquet engineering Higgs dynamics in time-periodic superconductors
• Third-harmonic generation in excitonic insulators
• Quench-drive spectroscopy of cuprates
• Long-lived Higgs modes in strongly correlated condensates
• Direct observation of the Higgs particle in a superconductor by non-equilibrium Raman scattering
• Proximity-induced collective modes in an unconventional superconductor heterostructure
• Theory of symmetry-resolved quench-drive spectroscopy: Nonlinear response of phase-fluctuating superconductors
• Terahertz amplifiers based on gain reflectivity in cuprate superconductors
• Phonon state tomography of electron correlation dynamics in optically excited solids
• Terahertz pulse-driven collective mode in the nematic superconducting state of Ba${}_{1-x}$K${}_x$Fe${}_2$As${}_2$
• Two-dimensional coherent spectroscopy of disordered superconductors in the narrow-band and broad-band limits