  Nuclear Coulomb potential at completely ionized and extremely thin atmosphere
can leaks to a macroscopic spatial scale. This effect is used to explain the
difference between the energy spectra of cosmic-ray electrons around $1 TeV$
measured by different experimental groups. The result inspires us to review the
traditional electromagnetic shower theory at the extreme conditions. It is also
reminds us that the energy spectrum of cosmic-ray electrons, which are measured
by Fermi-LAT and DAMPE at a higher altitude is more closer to a true signature.
