Table 1 Theoretical average teleportation fidelity as a function of linewidth, XX and X decay rates, fine-structure splitting (FSS), and g⁽²⁾(0) without temporal post-selection

QDs parameters	δ₂ = 2.1μeV, g⁽²⁾(0) ≠ 0	δ₂ = 0μeV, g⁽²⁾(0) ≠ 0	δ₂ = 2.1μeV, g⁽²⁾(0) = 0	δ₂ = 0μeV, g⁽²⁾(0) = 0
Linewidth > FL, \({\gamma }_{XX}/{\gamma }_{X}=1.4,\,{V}_{\rm{TPI}}^{\rm{Rmt}}=30\%\)	0.58 Present experiment without post-selection	0.58	0.60	0.60
Linewidth = FL, \({\gamma }_{XX}/{\gamma }_{X}=1.4,\,{V}_{\rm{TPI}}^{\rm{Rmt}}=59\%\)	0.67	0.67	0.70	0.72
Linewidth = FL, \({\gamma }_{XX}/{\gamma }_{X}=5,\,{V}_{\rm{TPI}}^{\rm{Rmt}}=83\%\)	0.73	0.77	0.83	0.85
\({V}_{\rm{TPI}}^{\rm{Rmt}}=100\%\)	0.84	0.87	0.95	0.99

First slot, current experimental parameters, with a two-photon interference (TPI) visibility of 30%, consistent with experimental results. Each row shows the impact of FSS and g⁽²⁾(0). TPI visibility can increase to \({V}_{{{\rm{TPI}}},\max }^{\,{\rm{Rmt}}\,}\) = 59% if Fourier-limited linewidths are considered. The radiative cascade still limits this value; nevertheless, average teleportation fidelities above the classical limit can be expected. Accelerating the biexciton decay selectively (so that γ_XX/γ_X = 5) can increase the TPI visibility to 83%. The last row shows the achievable fidelities for \({V}_{{{\rm{TPI}}},\max }^{\,{\rm{Rmt}}\,}\) = 100% as a function of FSS and g⁽²⁾(0). The following parameters were used: decay time of exciton τ_X = 171 ps, polarization mode overlap M_p = 1; when present, dephasing time T₂ = 35 ps, cross-dephasing time τ_HV = 10 ns, spin scattering time τ_ss = 10 ns, ratio of wanted three-fold coincidences to all detected three-fold coincidence k = 0.85.

Quick links

Search