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Bhupendra Subedi– University of Missouri Kansas City Kansas City, MO 64111 [email protected]

Carnot - efficiency based Nanoantenna Systems

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Page 1: Carnot - efficiency based Nanoantenna Systems

Bhupendra Subedi– University of Missouri Kansas City Kansas City, MO 64111

[email protected]

Page 2: Carnot - efficiency based Nanoantenna Systems

So any plasmonic nanostructures can be considered as nanoantennas (not very rigid)

Antenna: converts radiation energy to localized energy and vice versa

analogous to

phenomena in the surface of the metallic nanostructures (optical frequency) called Localized Surface Plasmon Resonance

(LSPR).

Page 3: Carnot - efficiency based Nanoantenna Systems

Wave strikes metal nanostructures, energy is transferredto electrons and resonance occurs when mom. of photons = mom of polaritons

[1] Javier Aizpurua, "Quantum kisses between optical nanoantennas”, mappingignorance (2013).

Page 4: Carnot - efficiency based Nanoantenna Systems

θ

ε1

ε2

E0x

y

Φ = Φ (r,θ ,ϕ ), scalar _ potentialE1 = − ∇ Φ 1and∇ 2Φ 1 = 0

E2 = − ∇ Φ 2and∇ 2Φ 2 = 0

We need to solve Laplace Equation

Page 5: Carnot - efficiency based Nanoantenna Systems

Electric Field in x direction is given by:

Φ 0 = −E0x = −E0rcosθ ,andΦ 2 = Φ scatter + Φ 0

Page 6: Carnot - efficiency based Nanoantenna Systems

Φdipole = p

4πε2cosθr2

= −E0rcosθ

Applied _Field = E0ε1 −ε2

ε1 +2ε2a3cosθr2

E0

x

y

ε1

ε2

Shows: Field outside = Field due to dipole + Applied_Field

Page 7: Carnot - efficiency based Nanoantenna Systems

So nanoantennas cover wide spectrum of applications

.# Areas of Application Application and devices

1. Nanophotonics detectors, filters and lasers eg. maskless optical lithography, NSOM

2. Plasmonic Solar Cells rectennas using ALD technology

3. Metamaterials optical/EM sheilding and invisibility cloaks

4. Chemical and bio/medical sensing and optical devices

super lenses for medical sensing, medical cancer treatment; gases and radiation sensors

5. On-Chip Interconnect on-chip nanoantennas

Page 8: Carnot - efficiency based Nanoantenna Systems

Need for different infrastructures such as modeling software and fabrication engineering

Conventional Antennas Nanoantennas

• Fed by real current, EM resonance causes waves

• Fed by localized current, Surface Plasmon Polaritons causes waves

• Demands classical treatment • Demands QM treatment

• Dissipated power related to voltage and current

• Dissipated power related to Green’s function tensor and Local density of state (LDOS)

Page 9: Carnot - efficiency based Nanoantenna Systems

Need for optimized antenna element and skin depth

• Long lifetime of exiton polariton causes recombination

P0

=I 2

3πη∆l

λ0

• Large ohmic losses and relative finite skin depth decreasing efficiency and

unfocussed radiation pattern

Page 10: Carnot - efficiency based Nanoantenna Systems

η =1− TcoldThot

Simple idea: Recycling of the wasted

heat from the cold sink

Page 11: Carnot - efficiency based Nanoantenna Systems

Hotter Sink gets more

hotter

Colder Sink gets

more colder

Increases

efficiency

Page 12: Carnot - efficiency based Nanoantenna Systems

1. Absorbing antenna as

close to Cold sink as possible

Say ¼ wave distance

=>short-circuit (unbalanced

Voltage condition)

Solution:

Coupling capacitance

Page 13: Carnot - efficiency based Nanoantenna Systems

Coupling Capacitance, A. Boswell, “amasci”

Tuned capacitive

Coupling

Improves power

Radiation by 100

folds

Avoids short-circuit; ehhances absorption

Page 14: Carnot - efficiency based Nanoantenna Systems

Nano-rectifiers

Not easy to channel heat radiations

These waves are vibrating in infra red or even THz frequency

that todays commercial rectifiers can’t handle

Nano-rectifiers 100-1,000 X smaller rectifiers needed

Page 15: Carnot - efficiency based Nanoantenna Systems

P0

=I 2

3πη∆l

λ0

Page 16: Carnot - efficiency based Nanoantenna Systems

Graphene based absorbing antenna

Fabry –Perot Resonance

Chamber (LSPR)

[Stamatios A. Et. Al]

Can be tuned to absorb certain wavelength

Page 17: Carnot - efficiency based Nanoantenna Systems

P0

=I 2

3πη∆l

λ0

[16] Maciej Klemm. "novel directional nanoantennas for single-emitter sources and wireless nano-links". International Journal of Optics, 2012(2012), 2012.

Page 18: Carnot - efficiency based Nanoantenna Systems

P0

=I 2

3πη∆l

λ0[1] Circuit implementation

[2] efficiency improvement

[3] good absorbing and radiating elements/ improvisation

Basically an idea,

I would do Modelling, FEKO Simulation, Implementation and what not.

Page 19: Carnot - efficiency based Nanoantenna Systems

P0

=I 2

3πη∆l

λ0

[1] Javier Aizpurua, "Quantum kisses between optical nanoantennas”, mappingignorance (2013).

[2] Javier Aizpurua, “Lecture given at SSOP Porquerolles, Sept. 2009

[3] Maciej Klemm. "novel directional nanoantennas for single-emitter sources and wireless nano-links". International Journal of Optics, 2012(2012), 2012

[4] A. Boswell, “amasci

Thank you