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Thursday, 21 February 2013 09:23

Surface Plasmon Vortices

 
 
 
MultiView 4000TM has been used to demonstrate the generation of surface plasmon vortices with arbitrary higher order vortex topological charges with novel plasmonic vortex lens (shown at the scheme below).

(a)-(d) and (e)-(h) are experimental NSOM images and simulations of the near-field distribution above the Plasmonic Vortex Lens at right-handed and left-handed circular polarization (respectively).

(c) Ez distribution of the near-field calculated by the RCWA. The number of node lines is five, which indicates that the topological charge of the SP vortex is l ) 5. The white arrows in (a)-(c) denote the directions of the rotation of the polarization. (d) Comparison of the intensity profiles. The red dashed line corresponds to the result of the theoretical model, i.e., the square of the absolute value of the fifth order Bessel function of the first kind. The blue solid line depicts the field intensity along the dashed line in the NSOM image. The black dotted line shows the field intensity along the dotted line in the RCWA image (Figure 3b). (e), (f), (g), and (h) correspond to (a), (b), (c), and (d), respectively, but from the left-handed circularpolarization beam.

Byoungho Lee et al Nano Lett. 2010, 10, 529-536  

   

Experimental setup for NSOM imaging of light distribution above Plasmonic Votrex Lens using Nanonics MultiView 4000TM system which has a free optical axis from top and bottom for bottom illumination of the sample and upright view (up to 100x) for tip-sample accurate positioning.

Byoungho Lee et al Nano Lett. 2010, 10, 529-536

 
Thursday, 21 February 2013 09:19

Cathode luminescence

Near Field Cathode Luminescence

Transparent AFM integration inside SEM and FIB chamber allows for unique protocols in NSOM cathode luminescence GaN nano wires

 

     
 

Near-field cathode luminescence from a GaN nanowire under ion beam excitation obtained with MultiView 2000TM in SEM chamber. On-line AFM (upper left) and NSOM (upper right) images obtained in collection mode. AFM/NSOM collage image is presented at bottom.
Baird et at, Physica B: Condensed Matter Volume 404, Issues 23-24, (2009)

 

 
     

 

 

Thursday, 21 February 2013 09:12

Multiple Imaging Modes

 AFM

 Raman

   

 NSOM

 Confocal

   
 Multiple Imaging modes of a transistor sample with the Nanonics MultiView series.

 AFM 3D

 Raman 3D

   

 NSOM 3D

 Confocal 3D

   

 AFM/NSOM Collage

 AFM/Raman Collage

   
Thursday, 21 February 2013 09:04

NSOM of Double Slit Plasmons

     

A: AFM topographic image of two slits on glass-coated gold surface imaged with AFM/NSOM fiber probe. The slits have 200nm width, 50nm thickness, 4µm length and 6µm separation.

B: NSOM image in collection mode with AFM/NSOM fiber probe (50nm aperture) shows transmitted light above the slits.

C: NSOM image shows the plasmons in the marked area between the two slits (see image B).

WSxM software has been used for image processing of the pictures above: I. Horcas et al. Rev. Sci. Instrum. 78, 013705 (2007).

• Nanonics’ MultiView systems with their tip-scanning capabilities and full integration with optical microscopes allow for efficient excitation and detection of plasmons. A dual optical microscope was used to obtain the above measurements. The lower microscope was used to excite the sample with a 532nm laser; the upper microscope was used to position the NSOM probe in the area of the slits.

 • AFM and NSOM images were simultaneously acquired with AFM/NSOM probe to obtain fully correlated topographic and NSOM data without any need to change the probe.

 • For the above measurements, it is critical to use tuning fork feedback to prevent any interference or background effects due to optical feedback.

Ideal systems for this application:
 1. MultiView 2000 
 2. MultiView 4000 
 3. CryoView 2000 

Thursday, 21 February 2013 08:41

NSOM Nanoarray Plasmons image

NSOM Nanoarray Plasmons image
 

A: NSOM collection mode image shows light distribution from an array of 136nm holes and spaces in gold. Illumination is from below with NSOM collection from above the aperture array. Arrow indicates polarization of the incident light with plasmonic propagation at 900 to the polarization. This demonstrates extraordinary transmission (EOT).

B: 3D Collage of the above NSOM image correlated with AFM topography. The distribution of light is more intense at the higher metal lines than in the apertures.

Michael Mrejen et al. OPTICS EXPRESS, Vol. 15, No. 15 (2007) 
WSxM software has been used for image processing of the pictures above: I. Horcas et al. Rev. Sci. Instrum. 78, 013705 (2007)

On-line multiple SPM Near-field Optical (NSOM) and Apertureless Near-field Optical (ANSOM or sSNOM )

Transparent Optical Integration
- Upright microscopes
- Inverted microscopes
- Dual 4pi configurations with illumination from above and below
- Side illumination with nano-aligned lensed fibers
- All Near-field modes: Transmission/Reflection/Collection/ Illumination Apertured (NSOM)/Apertureless and Scattering (sSNOM) protocols with MultiProbe online

Complex of Online Optical Measurements
- True Near-field /Far-field M2
- All Near-field modes of NSOM, ANSOM and sSNOM operation
- Near-field and Far-field characterization measurement

Tuning Fork Feedback 
- Ultra-sensitive feedback with high Q-factors
- Improved imaging quality
- Normal Force mode
- No interference due to optical feedback

Ideal systems for this application:
 1. MultiView 2000 
 2. MultiView 4000 
 3. CryoView 2000 

Thursday, 21 February 2013 08:45

High Current 50 mA NSOM & AFM

As the injection current is increased the laser heats up and there is an alteration in the topography of the laser which alters the light distribution. 

  NSOM light distribution

  AFM 20.5 mA

  AFM

  collage of AFM with light distribution

AFM & Light Distribution

Illustrated below: Distributed feedback laser structure, light distribution and collage of structure and light distribution at a low injection current.

 

AFM

 

AFM

 

light distribution 20.5 mA

 

collage AFM/light distribution

Near-field optics provides the capability to predict the near-field from far-field methods. 

Far-Field

 

Near-Field

 

The Distributed Feedback Laser AFM & NSOM Image at Higher Injection Currents (22.5 mA)

 

3D NSOM

 

collage of AFM with light distribution

 

Topography at 20.5mA 

 

 

Topography at 50mA (for comparison)

 

 NSOM Light Distribution

 

 Collage of AFM with Light Distribution

 

As the injection current is increased the laser heats up and there is an alteration in the topography of the laser which alters the light distribution. 

Thursday, 21 February 2013 08:34

Guided Light in a PBG Crystal

Zooming in with AFM on a Photonic Band Gap Structure

Photonic Band Gap materials or PBGs are important optical device structures for which NSOM is a critical characterizing tool .

 

 

(Left) 20x20um AFM image of the PBG crystal. Tapping mode with 40kHz resonance frequency.The boxed region is imaged to the right in an 8x8um scan. 
(Middle)  8x8 um AFM image of the boxed region in the 20 x 20um scan (left). 
(Right) 3.1x3.1um image of the boxed region in the 8x8um image to the left. 

 

 

PBG Topography Correlated with Light Concentration  In this PBG gaps develop between domains.

 

   
AFM topographic image of such a gap with a depth of ~3um.

 NSOM collection mode image of the same region with PBG illuminated from the bottom with a UV lamp.

 

 Collage 3D image of AFM topography and NSOM light distribution.  As is clearly seen the light is concentrated in the gap & clings preferentially to the walls.

 

 NSOM Collection Mode of Guided Light in a PBG

 

 

Green light in a domain (bright triangular region left) propagates in a gap that develops between two dark domains seen emanating from the triangular domain.

Thursday, 21 February 2013 08:30

NanoArray Plasmons Imaging

 
   

A: NSOM collection mode image shows light distribution from an array of 136nm holes and spaces in gold. Illumination is from below with NSOM collection from above the aperture array. Arrow indicates polarization of the incident light with plasmonic propagation at 900 to the polarization. This demonstrates extraordinary transmission (EOT).

B: 3D Collage of the above NSOM image correlated with AFM topography. The distribution of light is more intense at the higher metal lines than in the apertures.

Michael Mrejen et al. OPTICS EXPRESS, Vol. 15, No. 15 (2007) 
WSxM software has been used for image processing of the pictures above: I. Horcas et al. Rev. Sci. Instrum. 78, 013705 (2007)

On-line multiple SPM Near-field Optical (NSOM) and Apertureless Near-field Optical (ANSOM or sSNOM )

Transparent Optical Integration
- Upright microscopes
- Inverted microscopes
- Dual 4pi configurations with illumination from above and below
- Side illumination with nano-aligned lensed fibers
- All Near-field modes: Transmission/Reflection/Collection/ Illumination Apertured (NSOM)/Apertureless and Scattering (sSNOM) protocols with MultiProbe online

Complex of Online Optical Measurements
- True Near-field /Far-field M2
- All Near-field modes of NSOM, ANSOM and sSNOM operation
- Near-field and Far-field characterization measurement

Tuning Fork Feedback 
- Ultra-sensitive feedback with high Q-factors
- Improved imaging quality
- Normal Force mode
- No interference due to optical feedback

Ideal systems for this application:
 1. MultiView 2000 
 2. MultiView 4000 
 3. CryoView 2000 

Wednesday, 20 February 2013 14:51

High Current NSOM & AFM

As the injection current is increased the laser heats up and there is an alteration in the topography of the laser which alters the light distribution. 

  NSOM light distribution

  AFM 20.5 mA

AFM

collage of AFM with light distribution

AFM & Light Distribution

Illustrated below: Distributed feedback laser structure, light distribution and collage of structure and light distribution at a low injection current.

 

AFM

AFM

 

light distribution 20.5 mA

 

collage AFM/light distribution

Near-field optics provides the capability to predict the near-field from far-field methods. 

Far-Field

 

Near-Field

The Distributed Feedback Laser AFM & NSOM Image at Higher Injection Currents (22.5 mA)

3D NSOM

 

collage of AFM with light distribution

Topography at 20.5mA 

 

Topography at 50mA (for comparison)

NSOM Light Distribution

Collage of AFM with Light Distribution

As the injection current is increased the laser heats up and there is an alteration in the topography of the laser which alters the light distribution.

Wednesday, 20 February 2013 10:03

AFM Raman of CNT

 

 
   

Figure 1: (Left) AFM image shows an isolated nanowire of carbon nanotube on a Silicon surface . (Right) Online Raman map of the CNT nanowire obtained online pixel-by-pixel with the AFM image (left). The Raman map shows Raman integrated intensity between the carbon bands at 1540cm-1 and 1640cm-1.

Raman Mapping Parameters: Objective: 50 X LWD N.A=0.5 Raman step size (X & Y): 0,2 µm Laser 532 nm, grating: 600 l/mm Measurement time: 5s/point

WSxM software has been used for image processing of the pictures above: I. Horcas et al. Rev. Sci. Instrum. 78, 013705 (2007).

   

 

Figure 2: (Left) A CNT nanowire Raman map shows a band shift of the G-band along the nanowire (1575cm-1, green) and the graphite cluster aggregates (1580cm-1, red).