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Inside the Wavelength: seeing really small objects with light
Last modified: 2012-01-31
Abstract
Light, though our eyes, gives us the most direct means of observing the
world. Using a microscope we can see many objects invisible to the naked
eye, but even the microscope has its limitations: it is impossible with a
conventional microscope to resolve anything smaller than the wavelength of
light. Typically this sets a resolution limit of about 0.5 microns. To do
better than this and to Œget inside the wavelength¹ scientists have been
seeking a deeper understanding of light and its component electric and
magnetic fields in order to control these fields on a sub wavelength
scale. I shall report on schemes for harvesting light to a focus much
smaller than the wavelength and hence to very great energy density.
Practical limitations will be discussed and shown not to prevent
substantial enhancements to non linear phenomena and to spectroscopy.
world. Using a microscope we can see many objects invisible to the naked
eye, but even the microscope has its limitations: it is impossible with a
conventional microscope to resolve anything smaller than the wavelength of
light. Typically this sets a resolution limit of about 0.5 microns. To do
better than this and to Œget inside the wavelength¹ scientists have been
seeking a deeper understanding of light and its component electric and
magnetic fields in order to control these fields on a sub wavelength
scale. I shall report on schemes for harvesting light to a focus much
smaller than the wavelength and hence to very great energy density.
Practical limitations will be discussed and shown not to prevent
substantial enhancements to non linear phenomena and to spectroscopy.