Single or Entangled Photon Source
Patent 05051/TUB

The invention enables a simple and reproducible process for the production of a single or an entangled photon source, as used in quantum cryptography, the security industry or in communications and information technology.

  1. Free choice of electrically triggered entangled photon source and single photon source
  2. Thermo-electrical cooling
  3. Mass production possible
Possible Applications

The invention allows to produce a single photon source that can be used for quantum cryptography. Security Industry; Communication & Information Technology


Electrically triggered single or entangled photon sources are needed for high security quantum cryptography. In addition, the mass market requires efficient electrically driven high-speed devices. Common growth and processing techniques are used to fabricate single photon sources, which either generate polarization entangled photon pairs or polarization controlled single photons. This offers great opportunities to use single photons or entangled photon pairs for quantum cryptography.

Technical Description

We offer a method for producing a single or an entangled photon source which can be provided in a simple and reproducible manner. This novel method enables the production of a compact single photon source which can alternatively emit defined linearly polarized single photons, transposed photon pairs or cascades of correlated photons. The fine structure splitting of the exciton energy level of a quantum dot (QD) depends on material strains. The result ot the invention was to selectively establish the degree of strain within the quantum dots and within the surrounding material structure by the choice of the size of the QD.

Contact Us

Ina Krüger

Technology Transfer Manager

+49 (0)30 314-75916

Technology Readiness Level

Experimental proof of concept

Property Rights

approved: US, JP, DE

Patent Holder

Technische Universität Berlin

Possible Cooperation
  • Licensing
  • Patent Purchase
  • R&D Cooperation