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Quantum interference induced photon blockade in a coupled single quantum dot-cavity system.

Tang J, Geng W, Xu X - Sci Rep (2015)

Bottom Line: The photon blockade effect has a controllable flexibility by tuning the relative phase between the two pumping laser fields and the Rabi coupling strength between the quantum dot and the pumping field.Moreover, the photon blockade scheme based on quantum interference mechanism does not require a strong coupling strength between the cavity and the quantum dot, even with the pure dephasing of the system.This simple proposal provides an effective way for potential applications in solid state quantum computation and quantum information processing.

View Article: PubMed Central - PubMed

Affiliation: 1] Institute of Photo-electronic Thin Film Devices and Technology, Nankai University, Tianjin 300071, P. R. China [2] Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, P. R. China.

ABSTRACT
We propose an experimental scheme to implement a strong photon blockade with a single quantum dot coupled to a nanocavity. The photon blockade effect can be tremendously enhanced by driving the cavity and the quantum dot simultaneously with two classical laser fields. This enhancement of photon blockade is ascribed to the quantum interference effect to avoid two-photon excitation of the cavity field. Comparing with Jaynes-Cummings model, the second-order correlation function at zero time delay g((2))(0) in our scheme can be reduced by two orders of magnitude and the system sustains a large intracavity photon number. A red (blue) cavity-light detuning asymmetry for photon quantum statistics with bunching or antibunching characteristics is also observed. The photon blockade effect has a controllable flexibility by tuning the relative phase between the two pumping laser fields and the Rabi coupling strength between the quantum dot and the pumping field. Moreover, the photon blockade scheme based on quantum interference mechanism does not require a strong coupling strength between the cavity and the quantum dot, even with the pure dephasing of the system. This simple proposal provides an effective way for potential applications in solid state quantum computation and quantum information processing.

No MeSH data available.


(a) The minimum second-order correlation function  (dash-dotted red line) and  (solid blue line) as a function of the QD-cavity coupling strength g. (b) The ratio  is plotted as a function of the QD-cavity coupling strength g.
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f2: (a) The minimum second-order correlation function (dash-dotted red line) and (solid blue line) as a function of the QD-cavity coupling strength g. (b) The ratio is plotted as a function of the QD-cavity coupling strength g.

Mentions: By solving the time dependent master equation (see Methods), the second-order correlation function g(2)(0) was calculated with (without) the laser for pumping the quantum dot in QI (JC) model. Figure 2(a) shows the minimum values of g(2)(0) for JC model with Ω = 0, and of g(2)(0) for QI model with (Ω, θ) = (Ωopt, θopt) as a function of QD-cavity coupling strength g. Similar to the JC model, the second-order correlation function g(2)(0) monotonically decreases with increasing the coupling strength g, which suppresses the two-photon excitation due to a gradual increase of two-photon absorption energy gap Δ′. Surprisingly, photon blockade effect in the QI model is tremendously enhanced comparing with JC model at a specified coupling strength. For example, when log10g(2)(0) = −1.715 (as shown with the black-dashed line in Fig. 2(a)), the required coupling strength for JC model is g/κ = 12 while that for QI model is only 1.01. This indicates that a strong photon blockade can be achieved in a relative weak coupling strength in QI model.


Quantum interference induced photon blockade in a coupled single quantum dot-cavity system.

Tang J, Geng W, Xu X - Sci Rep (2015)

(a) The minimum second-order correlation function  (dash-dotted red line) and  (solid blue line) as a function of the QD-cavity coupling strength g. (b) The ratio  is plotted as a function of the QD-cavity coupling strength g.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4363868&req=5

f2: (a) The minimum second-order correlation function (dash-dotted red line) and (solid blue line) as a function of the QD-cavity coupling strength g. (b) The ratio is plotted as a function of the QD-cavity coupling strength g.
Mentions: By solving the time dependent master equation (see Methods), the second-order correlation function g(2)(0) was calculated with (without) the laser for pumping the quantum dot in QI (JC) model. Figure 2(a) shows the minimum values of g(2)(0) for JC model with Ω = 0, and of g(2)(0) for QI model with (Ω, θ) = (Ωopt, θopt) as a function of QD-cavity coupling strength g. Similar to the JC model, the second-order correlation function g(2)(0) monotonically decreases with increasing the coupling strength g, which suppresses the two-photon excitation due to a gradual increase of two-photon absorption energy gap Δ′. Surprisingly, photon blockade effect in the QI model is tremendously enhanced comparing with JC model at a specified coupling strength. For example, when log10g(2)(0) = −1.715 (as shown with the black-dashed line in Fig. 2(a)), the required coupling strength for JC model is g/κ = 12 while that for QI model is only 1.01. This indicates that a strong photon blockade can be achieved in a relative weak coupling strength in QI model.

Bottom Line: The photon blockade effect has a controllable flexibility by tuning the relative phase between the two pumping laser fields and the Rabi coupling strength between the quantum dot and the pumping field.Moreover, the photon blockade scheme based on quantum interference mechanism does not require a strong coupling strength between the cavity and the quantum dot, even with the pure dephasing of the system.This simple proposal provides an effective way for potential applications in solid state quantum computation and quantum information processing.

View Article: PubMed Central - PubMed

Affiliation: 1] Institute of Photo-electronic Thin Film Devices and Technology, Nankai University, Tianjin 300071, P. R. China [2] Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, P. R. China.

ABSTRACT
We propose an experimental scheme to implement a strong photon blockade with a single quantum dot coupled to a nanocavity. The photon blockade effect can be tremendously enhanced by driving the cavity and the quantum dot simultaneously with two classical laser fields. This enhancement of photon blockade is ascribed to the quantum interference effect to avoid two-photon excitation of the cavity field. Comparing with Jaynes-Cummings model, the second-order correlation function at zero time delay g((2))(0) in our scheme can be reduced by two orders of magnitude and the system sustains a large intracavity photon number. A red (blue) cavity-light detuning asymmetry for photon quantum statistics with bunching or antibunching characteristics is also observed. The photon blockade effect has a controllable flexibility by tuning the relative phase between the two pumping laser fields and the Rabi coupling strength between the quantum dot and the pumping field. Moreover, the photon blockade scheme based on quantum interference mechanism does not require a strong coupling strength between the cavity and the quantum dot, even with the pure dephasing of the system. This simple proposal provides an effective way for potential applications in solid state quantum computation and quantum information processing.

No MeSH data available.