@article {2559, title = {Modal aproximation for the electromagnetic field of a near-field optical probe.}, journal = {Applied Optics}, volume = {35}, year = {1996}, month = {1996 Jul 1}, pages = {3488-95}, abstract = {

A formalism is given in which the optical field generated by a near-field optical aperture is described as an analytic expansion over a complete set of optical modes. This vectoral solution preserves the divergent behavior of the near field and the dipolar nature of the far field. Numerical calculation of the fields requires only evaluation of a well behaved, one-dimensional integral. The formalism is directly applicable to experiments in near-field scanning optical microscopy when relatively flat samples are evaluated.

}, issn = {0003-6935}, doi = {10.1364/AO.35.003488}, author = {Grober, R D and Rutherford, T and Harris, T D} } @article {2561, title = {Dimensions of luminescent oxidized and porous silicon structures.}, journal = {Physical Review Letters}, volume = {72}, year = {1994}, month = {1994 Apr 18}, pages = {2648-51}, abstract = {

X-ray absorption measurements from H-passivated porous Si and from oxidized Si nanocrystals, combined with electron microscopy, ir absorption, α recoil, and luminescence emission data, provide a consistent structural picture of the species responsible for the visible luminescence observed in these samples. The mass-weighted average structures in por-Si are particles, not wires, with dimensions significantly smaller than previously reported or proposed.

}, issn = {1079-7114}, author = {Schuppler, S and Friedman, SL and Marcus, MA and Adler, DL and Xie, Y and Ross, FM and Harris, T D and Brown, WL and Chabal, YJ and Brus, LE and Citrin, PH} } @article {922, title = {Near-field spectroscopy of the quantum constituents of a luminescent system.}, journal = {Science}, volume = {264}, year = {1994}, month = {1994 Jun 17}, pages = {1740-5}, abstract = {

Luminescent centers with sharp (\<0.07 millielectron volt), spectrally distinct emission lines were imaged in a GaAs/AIGaAs quantum well by means of low-temperature near-field scanning optical microscopy. Temperature, magnetic field, and linewidth measurements establish that these centers arise from excitons laterally localized at interface fluctuations. For sufficiently narrow wells, virtually all emission originates from such centers. Near-field microscopy/spectroscopy provides a means to access energies and homogeneous line widths for the individual eigenstates of these centers, and thus opens a rich area of physics involving quantum resolved systems.

}, issn = {0036-8075}, doi = {10.1126/science.264.5166.1740}, author = {Hess, H F and Betzig, E and Harris, T D and Pfeiffer, L N and West, K W} } @article {2084, title = {Near-field spectroscopy of the quantum constituents of a luminescent system. (With commentary)}, journal = {Science}, volume = {264}, year = {1994}, month = {1994 Jun 17}, pages = {1740-5}, abstract = {

Luminescent centers with sharp (\<0.07 millielectron volt), spectrally distinct emission lines were imaged in a GaAs/AIGaAs quantum well by means of low-temperature near-field scanning optical microscopy. Temperature, magnetic field, and linewidth measurements establish that these centers arise from excitons laterally localized at interface fluctuations. For sufficiently narrow wells, virtually all emission originates from such centers. Near-field microscopy/spectroscopy provides a means to access energies and homogeneous line widths for the individual eigenstates of these centers, and thus opens a rich area of physics involving quantum resolved systems.

Commentary: Harald Hess and I joined forces, combining my near-field optical technology with his cryogenic scanned probe microscope to produce the first paper on high resolution spectroscopy beyond the diffraction limit. We discovered that the broad luminescence spectrum traditionally observed from quantum well heterostructures reflects a resolution-limited ensemble average of emission from numerous discrete sites of exciton recombination occurring at atomic-scale corrugations in the confining interfaces. With the combination of high spatial resolution from near-field excitation and high spectral resolution from cryogenic operation, we were able to isolate these emission sites in a multidimensional space of xy position and wavelength, even though their density was too great to isolate them on the basis of spatial resolution alone. This insight was very influential in the genesis of the concept (see above) that would eventually lead to far-field superresolution by PALM.

}, issn = {0036-8075}, doi = {10.1126/science.264.5166.1740}, url = {http://www.ncbi.nlm.nih.gov/pubmed/17839907}, author = {Hess, H F and Betzig, E and Harris, T D and Pfeiffer, L N and West, K W} } @article {2562, title = {Raman studies of steric hindrance and surface relaxation of stepped H-terminated silicon surfaces.}, journal = {Physical Review Letters}, volume = {71}, year = {1993}, month = {1993 Oct 4}, pages = {2280-83}, abstract = {

Polarized angle-resolved Raman spectra of the Si-H stretching vibrations on stepped H-terminated Si(111) surfaces confirm the constrained orientation of the step dihydride derived from ab initio cluster calculations. They further show that the step normal modes involve little concerted motion of the step atoms, indicating that step relaxation reduces the steric interaction much further than predicted.

}, issn = {1079-7114}, author = {Hines, MA and Chabal, YJ and Harris, T D and Harris, AL} } @article {2563, title = {Polarization contrast in near-field scanning optical microscopy.}, journal = {Applied Optics}, volume = {31}, year = {1992}, month = {1992 Aug 1}, pages = {4563-8}, abstract = {

Recent advances in probe design have led to enhanced resolution (currently as significant as \  12 nm) in optical microscopes based on near-field imaging. We demonstrate that the polarization of emitted and detected light in such microscopes can be manipulated sensitively to generate contrast. We show that the contrast on certain patterns is consistent with a simple interpretation of the requisite boundary conditions, whereas in other cases a more complicated interaction between the probe and the sample is involved. Finally application of the technique to near-filed magneto-optic imaging is demonstrated.

}, issn = {0003-6935}, doi = {10.1364/AO.31.004563}, author = {Betzig, E and Trautman, J K and Weiner, J S and Harris, T D and Wolfe, R} } @article {2564, title = {Breaking the diffraction barrier: optical microscopy on a nanometric scale.}, journal = {Science}, volume = {251}, year = {1991}, month = {1991 Mar 22}, pages = {1468-70}, abstract = {

In near-field scanning optical microscopy, a light source or detector with dimensions less than the wavelength (lambda) is placed in close proximity (lambda/50) to a sample to generate images with resolution better than the diffraction limit. A near-field probe has been developed that yields a resolution of approximately 12 nm ( approximately lambda/43) and signals approximately 10(4)- to 10(6)-fold larger than those reported previously. In addition, image contrast is demonstrated to be highly polarization dependent. With these probes, near-field microscopy appears poised to fulfill its promise by combining the power of optical characterization methods with nanometric spatial resolution.

}, issn = {0036-8075}, doi = {10.1126/science.251.5000.1468}, author = {Betzig, E and Trautman, J K and Harris, T D and Weiner, J S and Kostelak, R L} } @article {2095, title = {Breaking the diffraction barrier: optical microscopy on a nanometric scale. (With commentary)}, journal = {Science}, volume = {251}, year = {1991}, month = {1991 Mar 22}, pages = {1468-70}, abstract = {

In near-field scanning optical microscopy, a light source or detector with dimensions less than the wavelength (lambda) is placed in close proximity (lambda/50) to a sample to generate images with resolution better than the diffraction limit. A near-field probe has been developed that yields a resolution of approximately 12 nm ( approximately lambda/43) and signals approximately 10(4)- to 10(6)-fold larger than those reported previously. In addition, image contrast is demonstrated to be highly polarization dependent. With these probes, near-field microscopy appears poised to fulfill its promise by combining the power of optical characterization methods with nanometric spatial resolution.

Commentary: Introduced the adiabatically tapered single mode fiber probe to near-field scanning optical microscopy which, together with shear force feedback, made the technique a practical reality. Although earlier claims of superresolution via near-field microscopy existed for nearly a decade, this paper was the first to convincingly break Abbe{\textquoteright}s limit with visible light, as demonstrated by reproducibly resolving known, complex nanoscale patterns having features separated by much less than the wavelength. Whereas our fiber probe and shear force technologies were soon widely adopted and key to many novel applications (see above), the earlier methods proved to be technological dead ends, never achieving the results of their original claims. This experience taught me the most valuable lesson of my career: while it{\textquoteright}s bad to bullshit others, it{\textquoteright}s even worse to bullshit yourself. It{\textquoteright}s a lesson sadly unheeded by many current practitioners of superresolution microscopy.

}, issn = {0036-8075}, doi = {10.1126/science.251.5000.1468}, url = {http://www.ncbi.nlm.nih.gov/pubmed/17779440}, author = {Betzig, E and Trautman, J K and Harris, T D and Weiner, J S and Kostelak, R L} }