Strain-controlled quantum dot fine-structure for entangled-photon generation at 1550 nm

• Entangled-photon generation at 1550nm in the telecom C-band is of critical importance, since it enables the realization of quantum communication protocols over long distance using deployed telecommunication infrastructure. InAs epitaxial quantum dots have recently enabled on-demand generation of entangled pairs of photons in this wavelength range. However, time-dependent state evolution, caused by the fine-structure splitting, currently limits the fidelity to a specific entangled state. Here, we show suppression of the fine-structure for InAs quantum dots using micromachined piezoelectric actuators and demonstrate generation of highly entangled photons in the telecom C-band. At the lowest fine-structure setting, we obtain a maximum fidelity of (90.0 ± 2.7)% (concurrence of (87.5 ± 3.1)%). The concurrence remains high also for moderate (weak) temporal-filtering, with values close to 80% (50%), corresponding to 30% (80%) of collected photons, respectively. The presented fine-structure control opens the way for the exploitation of entangled photons from quantum dots in fiber-based quantum communication protocols.

Ämnesord

NATURVETENSKAP  -- Fysik -- Den kondenserade materiens fysik (hsv//swe)

NATURAL SCIENCES  -- Physical Sciences -- Condensed Matter Physics (hsv//eng)

Nyckelord

Optik och fotonik

Optics and Photonics

Publikations- och innehållstyp

vet (ämneskategori)

ovr (ämneskategori)