Field induced phase transition in the few photon regime

A D Panferov,A I Titov,B Kämpfer,A Otto,L Juchnowski,D B Blaschke,S A Smolyansky,S Bondarenko,A Malakhov,V Burov

doi:10.1051/epjconf/201713807004

Abstract

Some features of the field induced phase transition accompanied by the vacuum creation of an electron-positron plasma (EPP) in strong time-dependent electric fields have been discussed in the work [1] in the domain of the tunneling mechanism ($\omega \ll m$, where $\omega$ is the characteristic frequency of the external field and $m$ is the electron mass). In the present contribution the features of the this process will be considered in the few photon domain where $\omega \sim m$. We observe a narrowing of the transient domain of the fast oscillations and, mainly, a considerable growth of the effectiveness of the EPP production. Under these circumstances, we see an increase of the effectiveness of the EPP creation in the particular case of a bifrequent excitation, where both mechanisms (tunneling and few photon) act simultaneously [2,3].

Highlights

The present note is devoted to the investigation of some features of the dynamical Schwinger effect which concerns the creation of an electron-positron plasma (EPP) from the vacuum in fast varying spatially homogeneous external electric fields
On the examples of the simplest models for pulsed fields we demonstrate a significant increase of the efficiency of the EPP creation in the few photon domain for both, the distribution function and the observable pair density in the final state
We demonstrate the resonant behaviour of the residual distribution function fout(p) in the point p = 0 and the total residual EPP number density nout (3) as functions of the field pulse duration T of the field model (4)

Summary

Introduction

The present note is devoted to the investigation of some features of the dynamical Schwinger effect which concerns the creation of an electron-positron plasma (EPP) from the vacuum in fast varying spatially homogeneous external electric fields. The Schwinger effect was predicted for a constant electric field [4,5,6] According to these estimates a noticeable vacuum creation of electronpositron pairs in a strong electric field is possible only near the very high critical value of the field strength Ec = m2/e = 1.3 × 1016 V/cm. On the examples of the simplest models for pulsed fields we demonstrate a significant increase of the efficiency of the EPP creation in the few photon domain for both, the distribution function and the observable pair density in the final state. The reason for this enhancement is the Breit-Wheeler mechanism.

Kinetic equation

EPP creation in the few photon area

Findings

Conclusion