Controllable Photonic Time-Bin Qubits from a Quantum Dot
J. P. Lee, Louise Wells, Bruno Villa, Sokratis Kalliakos, Stevenson, RM, D. J. P. Ellis, Ian A. Farrer, D. A. Ritchie, Anthony J. Bennett, A. J. Shields · White Rose Research Online (University of Leeds, The University of Sheffield, University of York) · 2018
Photonic time-bin qubits are well suited to transmission via optical fibers and waveguide circuits. The states take the form 1(2)(α|0⟩+eiϕβ|1⟩), with |0⟩ and |1⟩ referring to the early and late time bin, respectively. By controlling the phase of a laser driving a spin-flip Raman transition in a single-hole-charged InAs quantum dot, we demonstrate complete control over the phase, ϕ. We show that this photon generation process can be performed deterministically, with only a moderate loss in coherence. Finally, we encode different qubits in different energies of the Raman scattered light, paving the way for wavelength-division multiplexing at the single-photon level.