US 5,473,157 A · Variable temperature near-field optical microscope

Abstract

An apparatus for optically imaging surfaces at low temperature is disclosed. The apparatus places a probe within the near-field distance of a sample. Both the sample and probe are placed in a low-temperature environment. The probe and sample are movable relative to each other to enable the entire surface of the sample to be imaged. The probe dithers with a certain amplitude and is positioned within the near-field distance by observing the change in the dither amplitude as the probe is placed in proximity to the sample surface. The sample is imaged by spectroscopically evaluating the light emitted from the surface of the sample. The low temperature environment is provided by a cryostat which is adapted to receive the sample and probe. The cryostat enables the sample to be imaged at temperatures as low as 1.5 K., thereby reducing some of the light loss associated with spectroscopic imaging techniques.

Claims13

Dependent claims

An apparatus for scanning at least a portion of the surface of a sample in a low temperature environment comprising:

a housing, a temperature controller that creates and maintains a temperature of about 1.5 K. to about 300 K. in the housing and, within the housing, a probe having a longitudinal axis and a tip, a positioner that positions the probe tip within a distance of one wavelength of light or less from a surface of the sample, and an oscillator that displaces the probe tip relative to the surface;
a photodetector;
and
a positioner controller that controls the position of the probe relative to the surface of the sample by imaging the probe tip onto the photodetector such that the changes in the oscillation of the probe tip are detectable by the photodetector.

1 more element

Dependencies are inferred from the claim text.

Variable temperature near-field optical microscope

Life of this patent

Variable temperature near-field optical microscope

Life of this patent

Abstract

Claims13