quantum biomimeticsnanotr16/notes/sganguly-1.pdf · 28 singlet yield plot has peaks at certain...

Quantum Biomimetics

Swaroop Ganguly, Vishvendra Poonia

Department of Electrical Engineering, IIT Bombay

29-Feb-2016HRI, Allahabad

Prologue: quantum mechanics in electronics

Quantum mechanics in biology - overview Photosynthesis Olfaction; In-Elastic Tunneling Spectroscopy …

…Avian Compass Overview State transitions & coherence Functional window Solid-state emulation: Diamond N-V centers

Conclusions

Outline

2

Quantum Mechanics in Electronic Devices

3

Quantum Effects

Covert

Bandstructure(m*) Scattering (µ)

Overt

Quantum Confinement Tunneling

http

://w

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tf.un

i-kie

l.de/

mat

wis

/am

at/s

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4

Quantum Effects

Covert


Overt


http://ww

w.mind-lam

p.com/inside-m

ind-lamp.php


5

Quantum Effects

Covert


Overt


ww

w.ir-nova.se

??

Pillarisetty et al., IEDM, 2010

Quantum Mechanics

6

ˆnn E nH ˆi t t

t

H

Time-dependent Time-independent

Schrödinger Equation (dynamical evolution: ‘normal’)

nn

c n System is in a ‘coherent’ superposition of energy eigenstates, until measured

Collapses to an eigenstate when measured (measurement: ‘weird’)

2 2nP n n c

Quantum Information Processing

7http://news.asiantown.net/r/33809/nsa-wants-to-build-a-super-quantum-computer-to-crack-all-encryptions-in-the-world

Simultaneous computing with and in logic gate

http://what-buddha-said.net/gallery/index.php/Science/bit_vs_qubit

0 1

No ‘measurement’ until computation is performed: tough

Quantum Information Processing

8

Simultaneous computing with and in logic gate0 1

No ‘measurement’ until computation is performed: tough

D-Wave ‘quantum computer’

Operates @ –273ºC

9

Quantum Mechanics in Biology - overview

10http://www.astrobio.net/topic/origins/extreme-life/photosynthesis-in-the-abyss/

Black Sea green sulphur bacteria: 3 photons per day per bacteriochlorophyll molecule!

Energy transfer from antenna to reaction center with η ≈ 1

Photosynthesis

Fourier transform:

Photosynthesis

11

Chin

et a

l., P

hil.

Tran

s. R

. Soc

., 20

12

Broadening due to environmental interaction 2E t

Energy-time Uncertainty

1 2t

Recall: QM level repulsion

12

00

0

0ˆ0

HUnperturbed Hamiltonian

Spectrum: eigenstates degenerate eigenvalues 1 0

,0 1

0

Perturbed Hamiltonian 0

0

ˆ

H

Spectrum: eigenstates eigenvalues 1 11 1,1 12 2 0

Photosynthesis

13

Chin

et a

l., P

hil.

Tran

s. R

. Soc

., 20

12

‘Phonon Antenna’

Olfaction

14

Shape Theory

https://www.newscientist.com/article/dn20130-fly-sniffs-molecules-quantum-vibrations/

Turin’s Vibration Theory

http://theconversation.com/whats-that-smell-a-controversial-theory-of-olfaction-deemed-implausible-42449

Olfaction

15

Jiaan

d G

uo, C

hem

. Soc

. Rev

., 20

13

In-Elastic Tunneling Spectroscopy (IETS)

Electronic alternative to optical methods (Raman, FTIR) integrated sensor?

Courtesy: A

shleshaP

atil

Olfaction

16

IETS: low temperature – for small thermal broadening of peaks

Sensor: Electron-energy filtering quantum confinement?

Reed, Materials Today, 2008

GaN wet-etched nanowire (Banerjee et al., APL 2015)

17

Avian Compass

18

Introduction

Magnetoreception: sensing of terrestrial magnetic field

Behavioral experiments @ FrankfurtLocal geomagnetic field = 46 µT

19

Behavioral Characteristics

Polarity compass only No North-South distinction

Operational in certain optical frequency range only

RF disruption Small (50nT) field transverse RF field (specific frequency

1.315 MHz) destroys compass action

Functional window Dynamic range: ± 30% of local geomagnetic field

20

Photo-generation of radicals

Spin state evolution of radical pair under local nuclear magnetic field and geomagnetic field

Radical pair recombination

The product depends on the spin state of radical

pair just before recombination

Ritz, Adem, & Schulten, Biophys. J. 78, 707 (2000)

Radical Pair (RP) Mechanism

21

RF field (1.316 MHz) disruption(cannot be magnetite…only)

One electron free from hyperfine

Hamiltonian

Hyperfine InteractionZeeman Interaction

Radical Pair (RP) Model

N. L

ambe

rt, e

t al.

Nat

ure

Phys

ics,

201

3.

22

Solov'yov, Schulten, SPIE New

sroom, 2009

Cryptochrome

E. M. G

auger, et al. PRL, 2011Radical Pair (RP) Model

23

RP System: 3-spin system 8-dimensional Hilbert space

Singlet and triplet channels: two ‘shelving’ states

Radical pair + Nucleus density matrix

Phenomenological Master Equation: density-matrix unitary evolution + environmental effects

RP Spin Dynamics

Phenomenological master equation for radical pairs

Initial State:

Radical pair state is singlet state:

Nuclear state is completely mixed state

And four similar operators corresponding to nuclear down

spin states

24

RP Spin Dynamics

25

0.00

0.25

0.50

0.75

1.00

/8 /4 3/8 /2

a/B=0.20

Spin

Yie

lds a/B=0.01

S Yield T0 Yield T+ Yield T- Yield

a/B=0.70

/8 /4 3/8 /2

a/B=10.00

/8 /4 3/8 /2

0.00

0.25

0.50

0.75

1.00

a/B=2.00a/B=1.00

000

Spin

Yie

lds

Singlet (S) and triplet (T0, T+, T-) yields vs. geomagnetic yield orientation for various hyperfine coupling strengths

State Transitions

State transitions for hyperfine and Zeeman

Hamiltonian interactions

Poonia et al., PRE 2015

26

Coherence & Entanglement

27

Singlet yield plot has peaks at certain field inclinations

Peak corresponds to dip in nuclear (intrinsic) decoherence

Coherence quantifier:

/8 /4 3/8 /20.6

0.8

1.0

Singlet Yield Relative Entropy of Coherence

Nor

mal

ized

Qua

ntity

a/B=1

0

(Nuclear) Decoherence

Poonia et al., PRE 2015

28

Singlet yield plot has peaks at certain field inclinations

Peak corresponds to dip in nuclear (intrinsic) decoherence

Peak disappears from nuclear state disentangled from RP

0.00

0.25

0.50

0.75

1.00

/8 /4 3/8 /20.00

0.25

0.50

0.75

1.00

/8 /4 3/8 /2 /8 /4 3/8 /2

Spi

n Y

ield

s

a/B=0.20

a/B=10.00

00

Spi

n Y

ield

s a/B=1.00

a/B=0.01

a/B=2.00

S Yield T0 Yield T+ Yield T- Yield

0

a/B=0.70

(Nuclear) Decoherence

29

Environmental (extrinsic) decoherence modeled with Lindblad noise operators, Master equation gets modified:

Γ: noise rate. Lindblad noise operators Li:

E. M. Gauger, et al. PRL 106.4 2011

(Environmental) Decoherence

30

/8 /4 3/8 /20.00

0.25

0.50

0.75

1.00

/8 /4 3/8 /2

0.00

0.25

0.50

0.75

1.00

/8 /4 3/8 /2

a/B=2

Sin

glet

Yie

ld

a/B=100

00

Sin

glet

Yie

ld

a/B=0.01 a/B=1a/B=0.50

s-1 xs-1 s-1

0

a/B=5

(Environmental) Decoherence

Sensitivity destroyed for larger noise rates Decoherence times > 10 µs

31

Functional Window

10-1 100 101 102 1030.0

0.1

0.2

0.3

0 50 100 150 200

0.14

0.16

0.18

0.20

0.22

Sen

sitiv

ity (D

S)

Magnetic Field (T)

/8 /4 3/8 /20.20

0.25

0.30

0.35

0.40

0.45

0.50

0

Sing

let Y

ield

Without RF field With RF field

Same biologically feasible parameter set yields: Functional window characteristic (but not sharp one) Adaptability of functional window to field variation RF disruption property Poonia et al., QuEBS 2014

G. B

alas

ubra

man

ian,

et a

l., N

at. M

ater

. 200

9

32

Bio-mimetics: spin dynamics in diamond

Nitrogen impurity + Vacancy (NV) centre, NV– state Ground and excited triplet states Intermediate singlet states Long coherence time (~ ms) at 300K

G. B

alas

ubra

man

ian,

et a

l., N

atur

e 20

08

33


0 100 200 300 400 500 6000.0

0.2

0.4

0.6

0.8

0 5 10 15 200.0

0.2

0.4

Popu

latio

n of

spin

sub

leve

ls

Time (ns)

ms = 0 ms = +1 ms = -1

Polarization and ODMR modeled using spin dynamics ~ RP

Poonia

et al., CTC

MP 2015

2.7 2.8 2.9 3.0 3.1

8.3 mT

5.8 mT

ms=

0 p

opul

atio

n

Frequency (GHz)

0 mT

2.8 mT

G. B

alas

ubra

man

ian,

et a

l., N

atur

e 20

08

34


DC magnetometry possible, for larger fields

Terrestrial field sensing presents detection challenges: limited by linewidth (50kHz ~ 20mG)

Feasibility of AC (nT) magnetometry, coherence effects TBD

2.7 2.8 2.9 3.0 3.1

8.3 mT

5.8 mT

ms=

0 p

opul

atio

n

Frequency (GHz)

0 mT

2.8 mT

Unexpected ‘cool’ physics in ‘warm’ environments

Potential for bio-mimetic ‘quantum engineering’ Efficient energy-harvesting Sensitive electronic nose Sensitive magnetometry

Goals Physics-based modeling of quantum biological system Modeling of potential quantum biomimetic systems Fabrication of quantum bio-mimetic devices

Conclusions

35

Students Ashlesha Patil (4th yr. DD) Utkarsh Sharma, Raunak Suryavanshi (3rd yr. DD)

Faculty Colleagues Dipankar Saha

Support Department of Electrical Engineering, IIT Bombay DeitY: Centre of Excellence in Nanoelectronics, Indian

Nanoelectronics Users Programme

Acknowledgments

36

37

THANK YOU!

quantum biomimeticsnanotr16/notes/sganguly-1.pdf · 28 singlet yield plot has peaks at certain...

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