Euclidean mirrors: enhanced vacuum decay from reflected instantons
arXiv:1706.06447 · doi:10.1088/1361-6471/aab5c4
Abstract
We study the tunneling of virtual matter-antimatter pairs from the quantum vacuum in the presence of a spatially uniform, time-dependent electric background composed of a strong, slow field superimposed with a weak, rapid field. After analytic continuation to Euclidean spacetime, we obtain from the instanton equations two critical points. While one of them is the closing point of the instanton path, the other serves as an Euclidean mirror which reflects and squeezes the instanton. It is this reflection and shrinking which is responsible for an enormous enhancement of the vacuum pair production rate. We discuss how important features of two different mechanisms can be analysed and understood via such a rotation in the complex plane. a) Consistent with previous studies, we first discuss the standard assisted mechanism with a static strong field and certain weak fields with a distinct pole structure in order to show that the reflection takes place exactly at the poles. We also discuss the effect of possible sub-cycle structures. We extend this reflection picture then to weak fields which have no poles present and illustrate the effective reflections with explicit examples. An additional field strength dependence for the rate occurs in such cases. We analytically compute the characteristic threshold for the assisted mechanism given by the critical combined Keldysh parameter. We discuss significant differences between these two types of fields. For various backgrounds, we present the contributing instantons and perform analytical computations for the corresponding rates treating both fields nonperturbatively. b) In addition, we also study the case with a nonstatic strong field which gives rise to the assisted dynamical mechanism. For different strong field profiles we investigate the impact on the critical combined Keldysh parameter. [...]
54 pages, 23 figures, revised, restructured to improve readability, matches journal version
References in corpus (23)
- Dynamically assisted Schwinger mechanism
- Worldline Instantons II: The Fluctuation Prefactor
- Momentum signatures for Schwinger pair production in short laser pulses with a sub-cycle structure
- Schwinger pair production in space- and time-dependent electric fields: Relating the Wigner formalism to quantum kinetic theory
- Interference Effects in Schwinger Vacuum Pair Production for Time-Dependent Laser Pulses
- The Schwinger mechanism revisited
- Pair Production Beyond the Schwinger Formula in Time-Dependent Electric Fields
- Holographic Schwinger effect in de Sitter space
- Electron-positron pair production in a bifrequent oscillating electric field
- Lifting shell structures in the dynamically assisted Schwinger effect in periodic fields
- Thermal Schwinger pair production at arbitrary coupling
- Strong laser fields as a probe for fundamental physics
- Optimization of Schwinger pair production in colliding laser pulses
- Dynamically assisted Sauter-Schwinger effect - non-perturbative versus perturbative aspects
- Dynamical Schwinger process in a bifrequent electric field of finite duration: survey on amplification
- Time-domain quantum interference in graphene
- Magnetic instability in AdS/CFT : Schwinger effect and Euler-Heisenberg Lagrangian of Supersymmetric QCD
- Pulse shape effects on the electron-positron pair production in strong laser fields
- Pulse shape optimization for electron-positron production in rotating fields
- Worldline holographic Schwinger effect
- Schwinger Pair Production at Finite Temperature in QED
- Quantum tunnelling from vacuum in multidimensions
- On Holographic Non-relativistic Schwinger Effect