Soft pair excitations and double-log divergences due to carrier interactions in graphene

Abstract

Interactions between charge carriers in graphene lead to logarithmic renormalization of observables mimicking the behavior known in (3+1)-dimensional quantum electrodynamics (QED). Here we analyze soft electron-hole (e-h) excitations generated as a result of fast charge dynamics, a direct analog of the signature QED effect - multiple soft photons produced by the QED vacuum shakeup. We show that such excitations are generated in photon absorption, when a photogenerated high-energy e-h pair cascades down in energy and gives rise to multiple soft e-h excitations. This fundamental process is manifested in a double-log divergence in the emission rate of soft pairs and a characteristic power-law divergence in their energy spectrum of the form $\frac{1}{\omega }\ln \left(\frac{\omega }{\Delta }\right)$. Strong carrier-carrier interactions make pair production a prominent pathway in the photoexcitation cascade.

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References in corpus (15)

• Universal Dynamic Conductivity and Quantized Visible Opacity of Suspended Graphene
• Dielectric function, screening, and plasmons in 2D graphene
• Dynamical polarization of graphene at finite doping
• The optical conductivity of graphene in the visible region of the spectrum
• Quantum critical point in graphene approached in the limit of infinitely strong Coulomb interaction
• Effect of electron-electron interactions on the conductivity of clean graphene
• Graphene via large N I: Renormalization
• Minimal conductivity in graphene: interaction corrections and ultraviolet anomaly
• Anomalous thermodynamics of Coulomb interacting massless Dirac fermions in two spatial dimensions
• Why does graphene behave as a weakly interacting system?
• Conductivity of interacting massless Dirac particles in graphene: Collisionless regime
• Effective field theory, three-loop perturbative expansion, and their experimental implications in graphene many-body effects
• Renormalization group flow of quartic perturbations in graphene: Strong coupling and large-N limits
• Velocity renormalization and anomalous quasiparticle dispersion in extrinsic graphene
• Photoexcitation Cascade and Quantum-Relativistic Jets in Graphene

Cited by in corpus (1)

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