Optical conductivity of semiconductor crystals with a screw dislocation

• We demonstrate ac electronic transport in semiconductor crystals with single screw dislocation.
• The conductivity shows a broad peak in the gigahertz frequency region.
• The peak position shifts to higher frequencies with increasing the Fermi energy.
• The results evidence distinct nature of dislocation from magnetic flux tubes, despite their formal similarity.

We study ac electronic transport in semiconductor crystals with a screw dislocation. The screw dislocation in the crystal results in an effective potential field that has a pronounced effect on the quantum mechanical electronic transport of the system. Alternating current conductivity at a frequency around 100 GHz has been calculated, showing upward shift in the peak position with increasing the Fermi energy. The result is in contrast to the persistency in the peak position observed in a dislocation-free crystal penetrated by magnetic flux, despite the apparent similarity between the two crystalline systems.