Abstract:
An electrically driven device for surface enhanced Raman spectroscopy includes a substrate, a Raman signal-amplifying structure positioned on the substrate, and an analyte receptor attached to a structure chosen from i) the Raman signal-amplifying structure, or ii) the substrate near the Raman signal-amplifying structure, or iii) combinations of i and ii. The analyte receptor has a selective binding affinity for an analyte. Conductive elements are positioned relative to one another and to the analyte receptor such that the conductive elements together produce an electric field in the vicinity of the analyte receptor when a voltage bias is applied between the conductive elements.
Abstract:
Polarization selective surface enhanced Raman spectroscopy (SERS) includes a plurality of nanofingers arranged as a SERS multimer to exhibit a polarization-dependent plasmonic mode and one or both of a stimulus source and a Raman detector. The stimulus source is to illuminate the SERS multimer with a stimulus signal and the Raman detector is to detect a Raman scattering signal emitted by an analyte in a vicinity of the SERS multimer. One or both of the Raman scattering signal has a polarization state dictated by or associated with the polarization-dependent plasmonic mode and the stimulus signal has a polarization state corresponding to the polarization-dependent plasmonic mode.
Abstract:
According to an example, methods for forming three-dimensional (3-D) nano-particle assemblies include depositing SES elements onto respective tips of nano-fingers, in which the nano-fingers are arranged in sufficiently close proximities to each other to enable the tips of groups of adjacent ones of the nano-fingers to come into sufficiently close proximities to each other to enable the SES elements on the tips to be bonded together when the nano-fingers are partially collapsed. The methods also include causing the nano-fingers to partially collapse toward adjacent ones of the nano-fingers to cause a plurality of SES elements on respective groups of the nano-fingers to be in relatively close proximities to each other and form respective clusters of SES elements, introducing additional particles that are to attach onto the clusters of SES elements, and causing the clusters of SES elements to detach from the nano-fingers.
Abstract:
A system includes an illumination source, a detector and a processor. The detector acquires spectral measurements of a sample under test under at least one varying condition. The processor processes the measurements to generate at least one spectral representation that includes Raman spectra and at least one spectral representation that includes non-Raman spectra.
Abstract:
According to an example, an apparatus for performing spectroscopy includes a perimeter wall extending between a first end and a second end of the perimeter wall along a first axis, in which an interior surface of the perimeter wall forms a hollow core extending along the first axis. The perimeter wall has openings at both the first end and the second end and light is to pass through the perimeter wall. The apparatus also includes a plurality of SES modules positioned around an inner circumference of the perimeter wall in a spaced arrangement with respect to each other to allow light to enter into the hollow core in gaps between the plurality of SES modules, in which each of the plurality of SES modules is positioned substantially across from a gap.
Abstract:
A scattering spectroscopy nanosensor includes a nanoscale-patterned sensing substrate to produce an optical scattering response signal indicative of a presence of an analyte when interrogated by an optical stimulus. The scattering spectroscopy nanosensor further includes a protective covering to cover and protect the nanoscale-patterned sensing substrate. The protective covering is to be selectably removed by exposure to an optical beam incident on the protective covering. The protective covering is to prevent the analyte from interacting with the nanoscale-patterned sensing substrate prior to being removed.
Abstract:
Polarization selective surface enhanced Raman spectroscopy (SERS) includes a plurality of nanofingers arranged as a SERS multimer to exhibit a polarization-dependent plasmonic mode and one or both of a stimulus source and a Raman detector. The stimulus source is to illuminate the SERS multimer with a stimulus signal and the Raman detector is to detect a Raman scattering signal emitted by an analyte in a vicinity of the SERS multimer. One or both of the Raman scattering signal has a polarization state dictated by or associated with the polarization-dependent plasmonic mode and the stimulus signal has a polarization state corresponding to the polarization-dependent plasmonic mode.
Abstract:
According to an example, apparatuses for performing multiple concurrent spectral analyzes on a sample under test include an optical system to concurrently direct a plurality of light beams onto analytes at multiple locations on the sample under test, in which the plurality of light beams cause light in either or both of a Raman spectra and a non-Raman spectra to be emitted from the analytes at the multiple locations of the sample under test. The apparatuses also include a detector to concurrently acquire a plurality of spectral measurements of the light emitted from the analytes at the multiple locations of the sample under test. Example methods of performing spectral analysis include use of the apparatuses.
Abstract:
Self-exciting surface enhanced Raman spectroscopy (SERS) employs an integral optical excitation source to provide an excitation signal to provide self-excitation of a SERS structure. The SERS structure includes a plurality of nanofingers having SERS-enhancing nanoparticles disposed adjacent to the nanofingers.
Abstract:
According to an example, an apparatus for collecting a material to be spectrally analyzed includes a body having a first end and a second end, in which the body is elongated along a first axis from the first end to the second end. The body also includes a hole having an opening formed in an external surface of the body at a location between the first end and the second end and extending at least partially through the body at an angle with respect to the first axis. The body further includes a plurality of surface-enhanced spectroscopy (SES) elements positioned inside the body.