Photon scanning-tunneling microscope

Sharp S L, Warmack R J, Goudonnet J P, Lee I and Ferrell T L 1993 Spectroscopy and imaging using the photon scanning-tunnelling microscope Acc. Chem. Res. 26 377... 

Shen, Y. R., Swiatkiewicz, J., Winiarz, J., Markowicz, P, and Prasad, P. N. 2000. Second-harmonic and sum-frequency imaging of organic nanocrystals with photon scanning tunneling microscope. App/. Phys. Lett. 77 2946 8. 

T Saiki, S Mononobe, M Ohtsu, N Saito, J Kusano. Tailoring a high-transmission hber probe for photon scanning tunneling microscope. Appl Phys Lett 68 2612-2614, 1996. 

Fig. 9.7 Setup of a PSTM (photon scanning tunneling microscope). Localized electromagnetic fields in the near field of the sample surface are detected with the help of a noncoated dielectric tip. Reprinted with permission from Rubahn (2004). Copyright 2004, B.G. Teubner Verlag.

In general, optically, electrically or chemically triggered switches would seem to be preferable to mechanically activated ones, as are photo-, electro- and chemo devices with respect to mechano devices and electronic or photonic computing with respect to mechanical computing. The ultimate in (nano)mechanical manipulation of a molecular device is represented by the realization of a bistable switch based on the motion of a single atom by means of the scanning tunnelling microscope [8.295] (see also Section 9.9). 

R. Berndt, R. Gaisch, J. K. Gimzewski, B. Reihl, R. R. Schlittler, W. D. Schneider and M. Tschudy, Photon-emission at molecular resolution induced by scanning tunneling microscope, Science 262, 1425 (1993). 

Nilius N, Ernst N, Freund HJ. Photon emission spectroscopy of individual oxide-supported silver clusters in a scanning tunneling microscope. Phys Rev I ett. 2000 84 3994-7. 

Berndt R, Gaisch R, Gimzewski JK, Reihl B, Schlittler RR, Schneider WD and Tschudy M (1993) Photon emission at molecular resolution induced by a scanning tunnelling microscope. Science 262 1425-1427. 

Commercially available photon tunneling microscopes have a lateral resolution of 160 nm but subnanometer vertical resolution. The nondestmctive, instantaneous 3-D viewing of a surface (no scanning) yields real-time imaging as one traverses a given sample. The sample must be a dielectric, but transparent polymer tepHcas of opaque samples can be studied. 

In the first part of the chapter several methods used to observe morphology of polymer blends are presented. Various optical microscopic methods are reviewed, including such modem techniques as photon tunneling microscopy (PTM), scanning near-field optical microscopy (SNOM), phase measurement interference microscopy (PMIM), surface plasmon microscopy (SPM) and optical waveguide microscopy (OWM). Many of these methods have been developed to study surfaces and thin films. However, they can also be applied to polymer blend morphology. 

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