experiments with entangled photons
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Experiments With Entangled Photons. Paulo Henrique Souto Ribeiro Instituto de Física - UFRJ. Summer School of Optics Concépcion January/2010. Quantum Optics Group at IF/UFRJ. Group members. Experiments: Prof. Paulo Henrique Souto Ribeiro Prof. Stephen Patrick Walborn Theory: - PowerPoint PPT PresentationTRANSCRIPT
Experiments With Entangled PhotonsPaulo Henrique Souto RibeiroInstituto de Fsica - UFRJSummer School of OpticsConcpcion January/2010
Quantum Optics Group at IF/UFRJ
Group membersExperiments:Prof. Paulo Henrique Souto Ribeiro Prof. Stephen Patrick Walborn
Theory:Prof. Luiz Davidovich Prof. Nicim ZaguryProf. Ruynet Matos FilhoProf. Fabricio Toscano
Msc and PhD students: Adriana Auyuanet Larrieu, Adriano H. de Oliveira Arago, Bruno de Moura Escher , Bruno Taketani, Daniel Schneider Tasca, Gabriel Horacio Aguilar, Osvaldo Jimenez farias, Gabriela Barreto Lemos, Rafael Chaves.
UFRJUFMGUSP-SO PAULOUFALUFF
Outline:
Part I-Simultaneity in parametric down-conversion-Violation of a classical inequality-Consequences of simultaneity: i)localized one-photon state; ii)the Hong-Ou-Mandel interferometer iii) measurement of the tunneling timePart II-Polarization entanglement-Bells inequalities -Entanglement measurement
Part III-Entanglement dynamics-Kraus operators-Entanglement sudden death-Process tomography-Evolution of entanglementPart VI-Spatial correlations-The transfer of the angular spectrum-Continuous variables etanglement- EPR paradox-Non-gaussian entanglement-Non-local optical vortex
Part I
- Simultaneity in parametric down-conversion
- Violation of a classical inequality
- Consequences of simultaneity:
i) localized one-photon state;
ii) the Hong-Ou-Mandel interferometer
iii) measurement of the tunneling time
Parametric Down-conversionEspontaneous emissionStimulated emissionTwinPhotons
Parametric Down-conversion
Observation of simultaneity
Observation of simultaneity
Parametric down-conversion: quantum stateTime evolutionTime evolution operatorTime integral
Simultaneity in parametric down-conversionQuantum state for weak interaction
Simultaneity in parametric down-conversionQuantum state including some approximations
Simultaneity in parametric down-conversionCalculation of expectation valuesElectric field operatorIntensityCoincidence
Simultaneity in parametric down-conversion:very simple view
Simultaneity in parametric down-conversion:very simple viewQuantum state: simple versionElectric field operator: plane wave, almost monochromaticCoincidence
Simultaneity in parametric down-conversion:very simple viewPlane wave pumping field
Coincidence detection
Coincidence detection
Measurement of time delayss=168pss=185ps
Simultaneity in parametric down-conversion:very simple view + detection filtersPlane wave pumping field
- Simultaneity in parametric down-conversion:very simple view + detection filtersInterference filter: typical Dl = 10nm, Dw = 3.8 x 1013 Hz, Dt = 82 fs
Simultaneity in parametric down-conversion:very simple view + timing resolution
Localized one photon state
Localized one photon state
Violation of a classical inequality
Violation of a classical inequality
Hong, Ou and Mandel Interferometer
Hong, Ou and Mandel Interferometer:single mode approachBeam splitterInput-output relations
Hong, Ou and Mandel Interferometer:single mode approachBeam splitterTwo-photon input stateCoincidence probability
Hong, Ou and Mandel Interferometer
Single-photon tunneling time
Part II
- Polarization entanglement
- Bells inequalities
- Entanglement measurement
Polarization entanglement:generationKwiat et al. PRL 75, 4337 (1995)
Kwiat et al. PRA 60, R773 (1999)White et al. PRL 83, 3103 (1999)Polarization entanglement:generation
Kwiat et al. PRA 60, R773 (1999)White et al. PRL 83, 3103 (1999)Polarization entanglement:generation
Mixed statePure entangled stateMixed states and entangled states
Detection of entanglement: violation of the Bell inequality
Bell-CHSH inequalityBell inequality and Bell states
Bell states for the photon polarizationCoincidence rate for f+:Bell inequality and Bell states
Bell states for the photon polarizationBell inequality and Bell statesCoincidence rate for f+:
Maximal violation Bell inequality and Bell states
Maximal violation Bell inequality and Bell states
Maximal violation Bell inequality and Bell states
Violation of a Bell inequality
Detects but does not quantify the entanglement properly - Some entangled states do not violate the Bell inequality Valid for dichotomic or dichotomized systems
Bell inequality and entanglement
Take a set of measurements :Reconstruction of the density matrixQuantum state tomography
Quantum state tomography
Quantum state tomography
Quantum state tomographyWith r12 one can compute all quantities related to the system
Concurrency:Direct measurement of entanglement
Mintert, Kus, and Buchleitner, Phys. Rev. Lett. 95 260502 (2005).
Direct measurement of entanglement using copies of states
Direct measurement of entanglement: pure statesPure stateTwo copiesMaximally entangled stateTwo copies
Experiment with entangled photons
Two copies of a state in a single photonPolarization state
Linear momentum stateTwo copies of a state in a single photon
Simultaneous entanglement in polarization and linear momentumTwo copies of a state in a single photon
Bell state projectionBell states combining momentum and polarization
C-NOT with a SAGNAC interferometer
Spatial rotations with cilyndrical lenses
Spatial rotations with cilyndrical lenses
Direct measurement of entangled with two copies
S. P. Walborn, P. H. Souto Ribeiro, L. Davidovich, F. Mintert, A. Buchleitner, Nature 440 1022 (2006)Direct measurement of entangled with two copies
S. P. Walborn, P. H. Souto Ribeiro, L. Davidovich, F. Mintert, A. Buchleitner, Nature 440 1022 (2006)Direct measurement of entangled with two copies
Part III
-Entanglement dynamics
-Kraus operators
-Entanglement sudden death
-Process tomography
-Evolution of entanglement
Entanglement dynamicsT. Yu, J. H. Eberly, Phys. Rev. Lett. 93, 140404 (2004). T. Yu, J. H. Eberly, Phys. Rev. Lett. 97, 140403 (2006).
Amplitude decay channel Quantum channel and Kraus map
Operadores de Kraus para o canal de amplitudeQuantum channel and Kraus operators
Amplitude decay channel for one photon polarization
Amplitude decay channel for one photon polarization
Amplitude decay channel for one photon polarization
Amplitude decay channel for one photon polarization
Amplitude decay channel for one photon polarization
Amplitude decay channel for one photon polarization
Amplitude decay channel for one photon polarization
Amplitude decay channel for one photon polarization
Amplitude decay channel for one photon polarization
Amplitude decay channel for one photon polarization
Amplitude decay channel for one photon polarization
Amplitude decay channel for one photon polarization
Amplitude decay channel for one photon polarization
Amplitude decay channel for one photon polarization
Amplitude decay channel for one photon polarization
Amplitude decay channel for one photon polarization
Amplitude decay channel for one photon polarization
Amplitude decay channel for one photon polarization
Amplitude decay channel for one photon polarization
Amplitude decay channel for one photon polarization
Kwiat et al. PRA 60, R773 (1999)White et al. PRL 83, 3103 (1999)Polarization entangled state
M. P. Almeida et al., Science 316, 579 (2007)Experimental observation of theentanglement sudden death
M. P. Almeida et al., Science 316, 579 (2007)Experimental observation of theentanglement sudden death
Process tomography
Reconstruction of the Kraus operators
T. Konrad et al., Nature Physics 4, 99 (2008).A dynamical law for the entanglement
A dynamical law for the entanglement
A dynamical law for the entanglement
A dynamical law for the entanglement
A dynamical law for the entanglement
O. Farias et al., Science 324, 1414 (2009)A dynamical law for the entanglement
O. Farias et al., Science 324, 1414 (2009)A dynamical law for the entanglement:experimental test
A dynamical law for the entanglement:generalization for mixed statesT. Konrad et al., Nature Physics 4, 99 (2008).
A dynamical law for the entanglement:generalization for mixed states
A dynamical law for the entanglement:generalization for mixed states
A. Jamiokowski, Rep. Math. Phys. 3, 275 (1972)
How to find $'A dynamical law for the entanglement:generalization for mixed states
O. Farias et al., Science 324, 1414 (2009)A dynamical law for the entanglement:generalization for mixed statesexperimental test
Part VI