Quantum Eraser

The quantum eraser model experiment is based on the design of the Mach-Zehnder interferometer. Polarizing filters in the Mach-Zehnder interferometer influence the interference behaviour because the interference capability depends on the polarization of the partial beams. In this setup, this effect can be observed for many photons. Theoretically, the observations can be transferred to the single photon case, whereby the measured intensities can be converted into probabilities.

On this page you will find all the information on the structure and special features of the modular quantum eraser model experiment as well as working materials for use in lessons.

Structure

Schematic Structure

Necessary modules:

 

Special Features

Effect of the polarizing filter

Up to five polarizing filters with different effects can be integrated into the setup:

  • Polarizing filter A: Laser diodes are typically linearly polarized and have a small non-polarized component. The polarizing filter A is used to filter out the non-polarized portion. The laser diode and polarizing filter A should therefore be aligned to each other so that as much light as possible is transmitted.
  • Polarizing filters B & C: Polarizing filter B and polarizing filter C are each positioned in one of the partial beams. If both polarizing filters are set at a 90° angle to each other, interference can no longer be observed. If both polarizing filters are set to the same angle (and are not rotated too far towards polarizing filter A), interference should be observed.
  • Polarizing filter D & E: Polarizing filter D and polarizing filter E can be used to ensure that interference can be observed again at the output, although polarizing filter B and polarizing filter C are aligned at a 90° angle to each other. To do this, polarizing filter D and polarizing filter E are rotated by 45° against polarizing filter B and polarizing filter C.

 

Working Materials

(German only)