NEAR-FIELDS�

LIGHT SOURCES�

(visible light)�propagating fields�(invisible light)�

evanescent fields�

λ

FARFIELD�

NEARFIELD�

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. . . . .

λ NA

Resolution limited to ~λ/2 �

Δx = 0.61 NA λ

E. Abbe, Arch. Mikrosk. Anat. 9, 413 (1873) �

IMAGING �

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BLOOD STAINS ON HUMAN HAIR �

Source: CSI MIAMI �

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Ca2+ PROTEINS IN RED BLOOD CELLS�

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Ca2+ PROTEINS IN RED BLOOD CELLS�

λ/2 �

Diffraction Limit !! �

protein

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. . . . .

NA

λ

Δx = 0.61 NA λ

Δk 4π

Δp h

Diffraction limit = Uncertainty principle Resolution limited by ~λ/2

UNCERTAINTY PRINCIPLE�

Physics Today, July (2011)�

Δx Δp = 15.3 h /2 > /2 h

LIGHT SOURCES�

(visible light)�propagating fields�(invisible light)�

evanescent fields�

λ

FARFIELD�

NEARFIELD�

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VISIBLE AND INVISIBLE LIGHT�

(visible light)�propagating fields�

λ λ

(invisible light)�evanescent fields�

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near-field� rescuer�

FREEING THE NEARFIELD �

invisible light �

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λ

near-field � rescuer�

invisible light �

FREEING THE NEARFIELD �

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DEMO �

EVANESCENT WAVES ?�

TOTAL INTERNAL REFLECTION �

relative index of refraction �

ñ > 1 �plane wave�evanescent wave�

real�imaginary�

Glass-air interface : �

ñ < 1 �

Critical angle : �

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TOTAL INTERNAL REFLECTION (TIR)�

Appl. Opt. 33, 7995 (1994)�

: , � complex ! �

Goos-Hänchen shift �

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FRUSTRATED TOTAL �INTERNAL REFLECTION �

�

�

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HOMEWORK� �

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. . . . .

NA

λ

Δx = 0.61 NA λ

Δk 4π

Δp h

Diffraction limit = Uncertainty principle Resolution limited by ~λ/2

UNCERTAINTY PRINCIPLE�

Physics Today, July (2011)�

Δx Δp = 15.3 h /2 > /2 h

SUB-WAVELENGTH LOCALIZATION �

<< λ

www.photonics.ethz.ch �

. . . . .

λ

Resolution is diffraction unlimited !!

antenna

Δd << λ

NA

evanescent waves: Δk > NA 4π / λ ~ 4π / Δd

UNCERTAINTY PRINCIPLE�

Physics Today, July (2011)�

NEAR-FIELD OPTICAL MICROSCOPY�

www.photonics.ethz.ch �

Rep. Prog. Opt. 50, 137-180 (2007)�Physics Today, July (2011)�

A. EINSTEIN (1928) �

SYNGE DEVELOPS REVISED CONCEPT (APERTURE) ! �

E.H. Synge, Phil.Mag. 6, 356 (1928)�

SYNGE’s PUBLICATION ! �

Rep. Prog. Opt. 50, 137-180 (2007)�Physics Today, July (2011)�

2001 FUJI-XEROX PATENT�

Rep. Prog. Opt. 50, 137-180 (2007)�Physics Today, July (2011)�

U. Ch. Fischer and D. W. Pohl, �Phys. Rev. Lett. 63, 458, 1989.���

J. Wessel, �JOSA B 2, 1538, 1985.���

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IMAGING OF SINGLE Ca+ ION CHANNEL �PROTEINS IN ERYTHROCYTE MEMBRANES�

C. Hoeppener

Nano Lett. 8, 642 (2008)�

IMAGING OF SINGLE Ca+ ION CHANNEL �PROTEINS IN ERYTHROCYTE MEMBRANES�

C. Hoeppener

Nano Lett. 8, 642 (2008)�

15 nm�

PRL 109, 017402 (2012)�

LOCALIZATION OF LIGHT�

LOCALIZATION OF FIELDS�

∼ λ/2

www.photonics.ethz.ch �

STRONGLY FOCUSED LIGHT�

Applications: (1) High NA objectives, (2) Solid Immersion Lenses, (3) Optical Tweezers, �" (4) Single Molecule Spectroscopy, (5) Confocal Microscopy, …�

Gaussian Beams�(paraxial optics, do not exist) �

Rigorous Beams�(angular spectrum representation) �

www.photonics.ethz.ch �

STRONGLY FOCUSED LIGHT�EXAMPLES: �

www.nano-optics.org �

LONG-RANGE SUBSURFACE IMAGING �OF INTEGRATED SILICON DEVICES �

Conventional 50X objective + AR! 10X objective with NAIL!

λ = 1064 nm λ = 1064 nm

Selim Unlu, Boston University�

www.nano-optics.org �

SUB-WAVELENGTH LOCALIZATION �

<< λ

www.photonics.ethz.ch �