Filtered Atomic Qubits Analysis of Photon-Mediated ... · • Coincident detection of photons after...
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Analysis of Photon-Mediated Entanglement Between Distinguishable Matter Qubits Introduction Filtered Atomic Qubits Solid-State Qubits Hybrid Qubits Conclusion Establishing Entanglement Protocol Analysis Selected References Quantum information promises extraordinary advances over classical means of both communication [1] and computation [2]. The resources required for both of these tasks may be established by photon-mediated long- distance probabilistic entanglement between quantum memories. While entanglement has been demonstrated between identical quantum memories [3-5], using distinguishable memories may be unavoidable when relying on fabricated devices such as optical cavities, solid-state qubits, and spectral filters. In the following sections I overview the implementation of the remote entanglement operation between two distinguishable quantum memories, and characterize the quality and efficiency of the protocol through a general analysis of the two- photon interference [*]. I then apply this protocol to a few selected systems for the entanglement of accessible pairs of quantum memories. These schemes may be implemented using previously demonstrated experimental techniques, and thus may be be accessible by experiments in the near-term. A robust two-photon interference protocol can be used to entangle distinguishable quantum memories with high fidelities and rates. A general analysis demonstrates that entanglement fidelities >99% and detection efficiencies >90% are, in principle, possible even with signicant mismatches in the frequency and temporal characteristics of the photons. By applying this analysis to three relevant systems, I illustrate both the utility of the calculations and their applicability to current experimental efforts. Moreover, my general analysis can be easily extended to other pairs of quantum memories. Overall, this evaluation elucidates the possibility of establishing remote entanglement between hybrid quantum memories that relies only on passive filtering and the passive stability inherent in the two-photon interference scheme. Ultimately, this type of stalwart architecture may be crucial for the realization of long-distance quantum communication and distributed quantum computation. Remote matter-matter entanglement is established with two processes: • Photon emission characterized by matter-photon entanglement • Coincident detection of photons after two-photon interference for entanglement swapping Although my analysis parallels to some extent the work in Refs. [6-7], I extend it to characterize entanglement fidelity and efficiency between two qubits distinguishable by frequency and temporal emission profiles [*]. Initialization by optical pumping Emission by spontaneous decay Excitation by pulsed laser Two-photon interference is evaluated by comparing two cases of a general joint detection probability where operator relationships relate output modes 3 and 4 to input modes 1 and 2. After interference and coincident detection we would observe photons in a post-selected maximally entangled Bell state which by entanglement swapping heralds the probabilistic matter-matter entanglement I characterize the fidelity (quality) of this entanglement observation in terms of visibility as I also define a two-photon detection efficiency General Results qubit 1 qubit 2 1 2 3 4 filter filter fiber fiber PMT PMT BS Entanglement may be established between two trapped 137 Ba + atoms using a filter in the path of both 137 Ba + emissions. Entanglement may be established between two nitrogen-vacancy (NV) centers using cavity- coupling to enhance emissions of both NV centers. Emitted photons are described by electric field operator and temporal mode profile Temporal Mode Frequency Mode Fourier Analysis Post-initialization excitation using microwave pulse and 637 nm laser pulse Spontaneous emission at 637 nm under influence of cavity- coupling and polarization filter State read-out with microwave pulse and beam resonant at 637 nm Hybrid entanglement may be achieved between an InAs quantum dot (QD) and a trapped 171 Yb + atom using a filter only in the path of QD emissions. Post-initialization excitation using 935 nm laser pulse Spontaneous emission at 935 nm under influence of spectral filter State read-out with beam resonant to single transition at 935 nm Post-initialization excitation using 297 nm laser pulse Spontaneous emission at 935 nm under influence of polarization filter State read-out with microwave pulse and beams resonant at 370 nm and 935 nm [*] A. M. Dyckovsky and S. Olmschenk, (2012), arxiv:1202.4028v1. [1] H. J. Kimble, Nature 453, 1023 (2008). [2] T. D. Ladd et al., Nature 464, 45 (2010). [3] C. W. Chou et al., Nature 438, 828 (2005). [4] D. N. Matsukevich et al., Phys. Rev. Lett. 96, 030405 (2006). [5] D. L. Moehring et al., Nature 449, 68 (2007). [6] S. Olmschenk et al., Int. J. Quant. Info. 8, 337 (2010). [7] T. Legero et al., Appl. Phys. B 77, 797 (2003). Post-initialization excitation using 493.5 nm laser pulse Spontaneous emission at 650 nm under influence of spectral and polarization filters State read-out with microwave pulse and beams resonant at 493.5 nm and 650 nm 137 Ba + Protocol NV Center Protocol QD Protocol 171 Yb + Protocol NV Center Results 137 Ba + Results Hybrid Results
Transcript of Filtered Atomic Qubits Analysis of Photon-Mediated ... · • Coincident detection of photons after...
Analysis of Photon-Mediated EntanglementBetween Distinguishable Matter Qubits
Introduction
Filtered Atomic Qubits
Solid-State Qubits
Hybrid Qubits
Conclusion
Establishing Entanglement
Protocol Analysis
Selected References
Quantum information promises extraordinary advances over classical means of both communication [1] and computation [2]. The resources required for both of these tasks may be established by photon-mediated long-distance probabilistic entanglement between quantum memories. While entanglement has been demonstrated between identical quantum memories [3-5], using distinguishable memories may be unavoidable when relying on fabricated devices such as optical cavities, solid-state qubits, and spectral filters. In the following sections I overview the implementation of the remote entanglement operation between two distinguishable quantum memories, and characterize the quality and efficiency of the protocol through a general analysis of the two-photon interference [*]. I then apply this protocol to a few selected systems for the entanglement of accessible pairs of quantum memories. These schemes may be implemented using previously demonstrated experimental techniques, and thus may be be accessible by experiments in the near-term.
A robust two-photon interference protocol can be used to entangle distinguishable quantum memories with high fidelities and rates. A general analysis demonstrates that entanglement fidelities >99% and detection efficiencies >90% are, in principle, possible even with signicant mismatches in the frequency and temporal characteristics of the photons. By applying this analysis to three relevant systems, I illustrate both the utility of the calculations and their applicability to current experimental efforts. Moreover, my general analysis can be easily extended to other pairs of quantum memories. Overall, this evaluation elucidates the possibility of establishing remote entanglement between hybrid quantum memories that relies only on passive filtering and the passive stability inherent in the two-photon interference scheme. Ultimately, this type of stalwart architecture may be crucial for the realization of long-distance quantum communication and distributed quantum computation.
Remote matter-matter entanglement is established with two processes:
• Photon emission characterized by matter-photon entanglement
• Coincident detection of photons after two-photon interference for entanglement swapping
Although my analysis parallels to some extent the work in Refs. [6-7], I extend it to characterize entanglement fidelity and efficiency between two qubits distinguishable by frequency and temporal emission profiles [*].
Initialization by optical pumping
Emission by spontaneous decay
Excitation by pulsed laser
Two-photon interference is evaluated by comparing two cases of a general joint detection probability
where operator relationships relate output modes 3 and 4 to input modes 1 and 2. After interference and coincident detection we would observe photons in a post-selected maximally entangled Bell state
which by entanglement swapping heralds the probabilistic matter-matter entanglement
I characterize the fidelity (quality) of this entanglement observation in terms of visibility as
I also define a two-photon detection efficiency
General Results
qubit 1 qubit 2
1 2
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filterfilter
fiber fiber
PMTPMT
BS
Entanglement may be established between two trapped 137Ba+ atoms using a filter in the path of both 137Ba+ emissions.
Entanglement may be established between twonitrogen-vacancy (NV) centers using cavity-coupling to enhance emissions of both NV centers.
Emitted photons are described by electric field operator
and temporal mode profile
Temporal Mode Frequency ModeFourierAnalysis
Post-initialization excitation using microwave pulse and 637 nm laser pulse
Spontaneous emission at 637 nm under influence of cavity-coupling and polarization filter
State read-out with microwave pulse and beam resonant at 637 nm
Hybrid entanglement may be achieved between an InAs quantum dot (QD) and a trapped 171Yb+ atomusing a filter only in the path of QD emissions.
Post-initialization excitation using 935 nm laser pulse
Spontaneous emission at 935 nm under influence of spectral filter
State read-out with beam resonant to single transition at 935 nm
Post-initialization excitation using 297 nm laser pulse
Spontaneous emission at 935 nm under influence of polarization filter
State read-out with microwave pulse and beams resonant at 370 nm and 935 nm
[*] A. M. Dyckovsky and S. Olmschenk, (2012), arxiv:1202.4028v1.[1] H. J. Kimble, Nature 453, 1023 (2008).[2] T. D. Ladd et al., Nature 464, 45 (2010).[3] C. W. Chou et al., Nature 438, 828 (2005).[4] D. N. Matsukevich et al., Phys. Rev. Lett. 96, 030405 (2006).[5] D. L. Moehring et al., Nature 449, 68 (2007).[6] S. Olmschenk et al., Int. J. Quant. Info. 8, 337 (2010).[7] T. Legero et al., Appl. Phys. B 77, 797 (2003).
Post-initialization excitation using 493.5 nm laser pulse
Spontaneous emission at 650 nm under influence of spectral and polarization filters
State read-out with microwave pulse and beams resonant at 493.5 nm and 650 nm
137Ba+ Protocol
NV Center Protocol
QD Protocol
171Yb+ Protocol
NV Center Results
137Ba+ Results
Hybrid Results
