Periodic Reporting for period 3 - DG-PESP-CS (Deterministic Generation of Polarization Entangled single Photons Cluster States)
Reporting period: 2019-06-01 to 2020-11-30
Despite the fact that quantum optics is a mature field with an impressive toolkit of devices for handling in particular photonic qubits, photons are unlikely to be the medium of choice for tasks that rely on localization and interactions between them. For example, 2-qubit gates rely on interactions between the qubits and therefore cannot be realized in a deterministic manner with photons alone. As a consequence, entangled states with only a limited number of photons have been demonstrated so far and only in a probabilistic manner.
We propose to overcome this problem by using confined electronic spin in a single semiconductor quantum dot. The electronic spin strongly interacts with light. Due to this interaction the spin will act as a needle in a knitting machine and it will entangle the polarization states of sequentially emitted single photons resulting from periodic optical excitation of the quantum dot confined electronic spin.
The overall objective of our proposal is therefore to demonstrate prototype devices, capable of deterministic generation of cluster states of polarization entangled photons.
Such cluster states are invaluable resources for quantum information processing.
Our research efforts resulted so far in 4 publications and about 25 invited conferences and workshops presentations.
We continue to develop our experimental setups and studies in order to achieve the following improvements until the end of the project:
a) Increasing the robustness of the entanglement beyond 5 qubits by enhancing the radiative rate of the biexciton decay, using the Purcell effect.
b) Demonstrating cluster states of higher dimensionality (entanglement connectivity) using coupled quantum dots.
c) Using the confined heavy-hole as entangler, thereby increasing the indistinguishability of the cluster state photons.