114
4 In the Field of Quantum Technologies
Fig. 4.7 High-repetition-rate deterministic single-photon output from a VECSEL-pumped
quantum-dot–microlens structure, as illustrated in Fig. 4.2. a Micro-PL spectrum of the quantum
emitter, here a positively charged exciton of a III/V quantum dot grown in Stranski–Krastanov
epitaxy mode. b Pump-dependent integrated intensity from the pulsed single-photon source. For
the highest flux acquired through the first lens of the setup, a maximum effective repetition rate of
143 MHz is obtained, which is lower than the 494 MHz of the optical pulse train from the VECSEL
owing to the quantum-dot lifetimes. c Temporal photon statistics measured at quantum-dot saturation (marked by red label in b) following spectral filtering (indicated by red arrows in a) with
normalised photon counts as a function of the delay time, reaching a minimum of 0.22 at τ = 0. A
clear antibunching with second-order temporal autocorrelation function value g (2) (0) < 0.03 well
below 0.5 according to the model (solid black line) is obtained. Further details on the experiment
and analysis are provided in [34]. The laser pulse train is displayed at the bottom. Dashed curves in
c model individual equidistant photon pulses represented by Lorentzian profiles (FWHM of 2.3 ns,
repetition rate 494 MHz, constant counts area per pulse for τ = 0). Reproduced with permission.
[34] Copyright 2015 AIP Publishing
emitters can be nowadays incorporated into flexibly 3D laser-written polymer (photoresist) matrices forming optical host structures for guidance or efficient out-coupling
[179, 180].
As briefly summarised in [181], such deterministic quantum-dot microlenses
delivered a platform for the exploration of the limits of photon indistinguishability by delay-time and temperature dependent Hong-Ou–Mandel experiments [182].
Furthermore, they paved the way towards entanglement swapping [183], for the
coherent control of the quantum-dot’s biexciton–exciton cascade [184], and for the
efficient generation of polarisation-entangled photon pairs [42].
4 In the Field of Quantum Technologies
Fig. 4.7 High-repetition-rate deterministic single-photon output from a VECSEL-pumped
quantum-dot–microlens structure, as illustrated in Fig. 4.2. a Micro-PL spectrum of the quantum
emitter, here a positively charged exciton of a III/V quantum dot grown in Stranski–Krastanov
epitaxy mode. b Pump-dependent integrated intensity from the pulsed single-photon source. For
the highest flux acquired through the first lens of the setup, a maximum effective repetition rate of
143 MHz is obtained, which is lower than the 494 MHz of the optical pulse train from the VECSEL
owing to the quantum-dot lifetimes. c Temporal photon statistics measured at quantum-dot saturation (marked by red label in b) following spectral filtering (indicated by red arrows in a) with
normalised photon counts as a function of the delay time, reaching a minimum of 0.22 at τ = 0. A
clear antibunching with second-order temporal autocorrelation function value g (2) (0) < 0.03 well
below 0.5 according to the model (solid black line) is obtained. Further details on the experiment
and analysis are provided in [34]. The laser pulse train is displayed at the bottom. Dashed curves in
c model individual equidistant photon pulses represented by Lorentzian profiles (FWHM of 2.3 ns,
repetition rate 494 MHz, constant counts area per pulse for τ = 0). Reproduced with permission.
[34] Copyright 2015 AIP Publishing
emitters can be nowadays incorporated into flexibly 3D laser-written polymer (photoresist) matrices forming optical host structures for guidance or efficient out-coupling
[179, 180].
As briefly summarised in [181], such deterministic quantum-dot microlenses
delivered a platform for the exploration of the limits of photon indistinguishability by delay-time and temperature dependent Hong-Ou–Mandel experiments [182].
Furthermore, they paved the way towards entanglement swapping [183], for the
coherent control of the quantum-dot’s biexciton–exciton cascade [184], and for the
efficient generation of polarisation-entangled photon pairs [42].