Boston University MRI – Development of a Holographic Nanoscale Optics Facility

Development of a Holographic Nanoscale Optical Facility

Sub-20nm optical resolution with both amplitude and phase to holographically map 3D electric field distribution in the near-field

Wide wavelength range; Operates in reflection and transmission, includes elastic scattering, Raman and flourescence

Research on nano-plasmonics and nano-biosystems for sensing and detection

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Bennett B. Goldberg, Trustees of Boston University, DMR 1429437

Boston University MRI – Development of a Holographic Nanoscale Optics Facility

NSOM Studies of Aluminum Nanoantennas

Progress:

Develop & study Al nanoantennas via MRI funded NSOM system (under development).

Advantages of Aluminum plasmonics• Promising for UV & Vis nanoantennas –

higher plasma freq. vs. Au, Ag, Cu• CMOS process friendly material.• Reduced cost.

Bennett B. Goldberg, Trustees of Boston University, DMR 1429437

Simulated Near-Fields (Intensity & E-z component)

|E|2 |Ez|

NSOM Probes This

Nanoantenna test samples fabricated at BU

Boston University MRI – Development of a Holographic Nanoscale Optics Facility

NSOM Modeling Tools, Contrast Improvement & Polarization Selectivity

Object Near-Fields Simulated NSOM Measurements

Crossed polarizer No polarizer

Background overwhelms tip

signal

NSOM signal depends on complex interaction (coupling) between NSOM tip & sample. Also influenced by illumination focal fields.• Developed tools combining semi-analytical methods with numerical

(FDTD) tools to model NSOM signal.• Enables accurate prediction & design of experiments, interpretation of

data.• Proposed methods using polarization to improve NSOM contrast &

extract specific near-field components. Validated w/ modeling (experiment in progress). (Below).

Bennett B. Goldberg, Trustees of Boston University, DMR 1429437