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Imperial College London. Principles of Noise Assisted Transport in Networks. Martin B Plenio. Institute for Mathematical Sciences & Quantum Optics and Laser Science Group Blackett Laboratory Imperial College London http://www.imperial.ac.uk/quantuminformation. - PowerPoint PPT Presentation
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Imperial College London
Institute for Mathematical Sciences&
Quantum Optics and Laser Science GroupBlackett Laboratory
Imperial College London
http://www.imperial.ac.uk/quantuminformation
Principles of Noise Assisted Transport in Networks
Martin B Plenio
In collaboration with: Animesh Datta & Filippo Caruso (Imperial College London, UK) Alex Chin and Susana Huelga (Univ. Hertfordshire, UK)
Lisbon, 8th July 2009
Lisbon, 8th July 2009
Lisbon, 8th July 2009
Lisbon, 8th July 2009
Lisbon, 8th July 2009
Lisbon, 8th July 2009
Lisbon, 8th July 2009
Noise seems a problem here as it destroys quantum coherence
Lisbon, 8th July 2009
Weak coherent driving
Weak response
Lisbon, 8th July 2009
Weak coherent driving + weak noise give a strong coherent response.
Stochastic resonance
Noise
Lisbon, 8th July 2009
Biological systems can use noise to improve their sensitivity to weak coherent signals
Can we use this in quantum mechanics ?
Noise can be good for you in quantum mechanics too for entanglement generation and preservation !
Huelga & Plenio, PRA 1999, PRA 2000 & PRL 2002 & PRL 2007
See also overview talk by Susana Huelga Friday
Lisbon, 8th July 2009
Clicks
Time
Clicks
Time
A Fundamental Experiment
Lisbon, 8th July 2009
A Fundamental Experiment
Lisbon, 8th July 2009
Clicks
Time
Clicks
Time
A Fundamental Experiment
Lisbon, 8th July 2009
Green sulphur Bacteria
Photosynthesis
A black smoker in the Atlantic Ocean ~ 2000m deep
Y.C. Cheng and G.R. Fleming, Annu. Rev. Phys. Chem. 60, 241 (2009)
Lisbon, 8th July 2009
Green sulphur Bacteria
Exciton Transport in Photosynthesis
Reaction Centre
CO2+ 2 H S2
+ energy
CH O2
+ 2 S + H O2
Lisbon, 8th July 2009
Green sulphur Bacteria
Reaction Centre
Exciton Transport in Photosynthesis
CO2+ 2 H S2
+ energy
CH O2
+ 2 S + H O2
Lisbon, 8th July 2009
Transfer to reaction centre
Green sulphur Bacteria
Reaction Centre
Exciton Transport in Photosynthesis
CO2+ 2 H S2
+ energy
CH O2
+ 2 S + H O2
Lisbon, 8th July 2009
Loss of excitation
Transfer to reaction centre
Reaction Centre
CO2+ 2 H S2
+ energy
CH O2
+ 2 S + H O2
M.B. Plenio and S.F. Huelga, New J. Phys. 10, 113019 (2008)
Exchange of excitation
Dephasing
Lisbon, 8th July 2009
Noise Assisted Transport and Photosynthesis
No dephasing
Some dephasing
Plenio & Huelga, New J. Phys. 2008 Mohseni, Rebentrost, Lloyd, Aspuru-Guzik, J. Phys. Chem. 2008
More dephasing
Lisbon, 8th July 2009
Physical Origin of Noise Assisted Transport
Lisbon, 8th July 2009
Exciton Transport in Photosynthesis
Show Movie 1: No dephasing Initial excitation in site 1
Lisbon, 8th July 2009
Two differenttime scales !
Exciton Transport in Photosynthesis
Lisbon, 8th July 2009
Clicks
Time
Clicks
Time
Destructive Interference and Invariant States
Lisbon, 8th July 2009
Destructive Interference and Invariant States
J J
Reactioncenter
=
Lisbon, 8th July 2009
Destructive Interference and Invariant States
Tran
sfer
eff
icie
ncy
J J
=
Reactioncenter
Lisbon, 8th July 2009
Noise Inhibits Destructive Interference
Decoherence inhibits destructive interference !
Tran
sfer
eff
icie
ncy
Reduction ofdestructive interference
J J
Reactionscenter
Reactioncenter
=
Lisbon, 8th July 2009
Destructive Interference and Invariant States
Invariant state:
Two atoms in the same location:
Lisbon, 8th July 2009
Dephasing on site 1 only
Show Movie1a: Small dephasing on site 1 only
Lisbon, 8th July 2009
Dephasing on site 1 only
Lisbon, 8th July 2009
Destructive Interference and Invariant States
not invariant under Hamiltonian evolution !
Different energy splitting:
Lisbon, 8th July 2009
Static disorder inhibits destructive interference !
Disorder Inhibits Destructive Interference
J J
J JDestructiveinterference
Reactioncenter
Reduction ofdestructive interference
Reactioncenter
Lisbon, 8th July 2009
Disorder Inhibits Destructive Interference
Lisbon, 8th July 2009
The Hamiltonian of the FMO complex
Quite strong static disorder compared to coupling strengths !
Lisbon, 8th July 2009
Bridging the gap: Enhanced transport via line broadening
Lisbon, 8th July 2009
Dephasing Noise on Site 3 only
Play Movie1b: Dephasing noise only on site 3
Play Movie1ab: Same amount of dephasing noise now only on site 3
Lisbon, 8th July 2009
Dephasing Noise on Site 3 only
Lisbon, 8th July 2009
No line broadening, No transfer!Line broadening does enhance transfer!
Lisbon, 8th July 2009
J J
destructive interference
-J -J
Spatially Correlated Noise
effect ofnoise reduced
J J
destructive interference
+J -J
effect ofnoise enhanced
Lisbon, 8th July 2009
local dephasing without correlations
dephasing with non-local correlations
T=5 ps
Therefore, correlated noise does not lead to decisive improvements in this setting!
Spatially Correlated Noise
Lisbon, 8th July 2009
J J
destructive interference
J J
Loss Enhanced Transport
destructive interference
reduced
J J
excitationlost
Lisbon, 8th July 2009
Noise Assisted Transport and Photosynthesis
No dephasing
Some dephasing
More dephasing
Lisbon, 8th July 2009
Reduction of destructive interference
Inhibition of coupling through dephasing
Dependence on Noise Strength
Lisbon, 8th July 2009
Two differenttime scales !
Robustness against strong static disorder compared to coupling strengths (i.e. 20%)!
optimal dephasing
no dephasing
Robustness of Noise Assisted Transport
Lisbon, 8th July 2009
F.Caruso., A.W. Chin, A. Datta, S.F. Huelga, M.B. Plenio, to be submitted
Entanglement Dynamics
Lisbon, 8th July 2009
F.C., A.W. Chin, A. Datta, S.F. Huelga, M.B. Plenio, arxiv:0901.4454 (2009)
|01>-|10>
J J
reduced destructive interferencedestructive interference
J
Each process open additional pathways for propagation
Lisbon, 8th July 2009
The Fundamental Mechanisms
Dephasing can reduce destructive interference
Energy mismatch can reduce destructive interference
Dephasing noise increases overlap of energy levels
Each process open additional pathways for propagation
Plenio & Huelga, New J. Phys. 10, 113019 (2008)Caruso, Chin, Datta, Huelga, Plenio, arxiv:0901.4454 [quant-ph]
Lisbon, 8th July 2009
Can we improve solar cellsbased on this idea ?
More generally: Adding the right kind of noise, to the right kind of nano-structure can improve its performance.
Engineer system to generate constructive interplay between quantum dynamics and noise
Lisbon, 8th July 2009
This talk was based on
Plenio & Huelga, New J. Phys. 10, 113019 (2008)
Caruso, Chin, Datta, Huelga, Plenio, E-Print arXiv:0901.4454
Caruso, Chin, Datta, Huelga, Plenio, to be submitted
Lisbon, 8th July 2009
We move to Ulm to establish Center for Quantum Engineering
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