Memory Cell for Data Storage – II

10004/TUB: Memory Cell for Data Storage – II


For a secure data transmission while using quantum cryptography, the emission of single photons is essential. Emitting more than one photon at a time leads to photon number splitting (PNS), which allows eavesdropping.

One approach to avoid this problem is to use a vertical-cavity surface-emitting laser (VCSEL) to excite quantum dots (QD) which only emit single photons. This technique allows the tuning of VCSEL cavities by external stress using piezoelectric actuators.

The lateral and the vertical expansion of the actuator controls the cavity modes and QD emission wavelengths. This allows the resonant tuning of the VCSEL with the QD excitons. The yield of single photons is also increased by using higher operating frequencies and by a significant reduction of empty pulses.

Anwendungsmöglichkeiten / Possible applications:

The invention is applicable for quantum cryptography and for data transmission as used in the communication industry.

Interested? Contact Us! Interested? Contact Us!
Show all techoffers Vorteile / Benefits:
  • Highly increased yield of single photons
  • High Purcell and quality factors
  • Compensation of temperature fluctuation
Entwicklungsstand / Development status:


Reifegrad / Maturity level:


Schlagworte / Tags:
data transmission, photon emitter, quantum dots, VCSEL
Schutzrechte / Property rights:

US - granted; EP - pending

Patentinhaber / Patent holder:

Technische Universität Berlin

Möglichkeiten der Zusammenarbeit / Possible cooperation:
  • R&D Cooperation
  • Patent Purchase
  • Licensing

Ansprechpartnerin / Contact Person:
Ina Krüger

Tel.: 030 314-75916
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