Quantum Dots and Microcavities

In this project we study the building blocks of photonic quantum information processing. To do so we create devices at the intersection of quantum information science, materials science and electronics with the goal of implementing single photon generation, entangled photon generation and quantum gate operations.

When a quantum dot (an atom-like emitter with discrete energy levels) is embedded between two mirrors, nearly all of the light emitted from the dot can be captured and measured. With the use of a P-I-N diode one can tune the resonance frequency of a quantum dot to that of the cavity resonance, and we use such a scheme to realize high efficiency, high purity single photon sources. Moreover, a singly charged exciton can be used as a solid-state qubit that couples strongly to a photonic qubit. With such a device, one could perform photonic gate operations such as a CNOT gate.

We are currently pursuing the generation of entangled photons via spontaneous parametric down conversion in GaAs/AlGaAs microring resonators embedded in SiO2. By tuning the size and layer structure of a GaAs/AlGaAs ring resonator, one can control the effective index of various guided modes and realize different allowed parametric processes. It is our hope that such a device can be used to create entangled photons in an AlGaAs-on-silicon platform.


Recent publications

Polarized quantum dot cavity-QED and single photons
HJ Snijders, DNL Kok, MF van de Stolpe, JA Frey, J Norman, AC Gossard, JE Bowers, MP van Exter, D Bouwmeester, W Löffler
arXiv preprint arXiv:1811.10571

Polarization tuning for high-fidelity fiber-coupled single photon sources
JA Frey, HJ Snijders, J Norman, AC Gossard, JE Bowers, W Löffler, D Bouwmeester
Quantum Photonic Devices 2018 10733, 107330H

Electro-optic polarization tuning of microcavities with a single quantum dot
JA Frey, HJ Snijders, J Norman, AC Gossard, JE Bowers, W Löffler, D Bouwmeester
Optics letters 43 (17), 4280-4283

Observation of the unconventional photon blockade
HJ Snijders, JA Frey, J Norman, H Flayac, V Savona, AC Gossard, JE Bowers, MP van Exter, D Bouwmeester, W Löffler
Physical review letters 121 (4), 043601

Single photons and unconventional photon blockade in quantum dot cavity-QED
HJ Snijders, JA Frey, J Norman, H Flayac, V Savona, AC Gossard, JE Bowers, MP van Exter, D Bouwmeester, W Löffler
arXiv preprint arXiv:1803.10992

Fiber-coupled cavity-QED source of identical single photons
H Snijders, JA Frey, J Norman, VP Post, AC Gossard, JE Bowers, MP van Exter, W Löffler, D Bouwmeester
Physical Review Applied 9 (3), 031002