Abstract: Devices to detect a substance and methods of producing such a device are disclosed. An example device to detect a substance includes a housing defining a first chamber and a substrate coupled to the housing. The substrate includes nanostructures positioned within the first chamber. The nanostructures are to react to the substance when exposed thereto. The device includes a first heater positioned within the first chamber. The heater is to heat at least a portion of the substance to ready the device for analysis.

Abstract: A method for forming a surface-enhanced fluorescence spectroscopy (SEFS) apparatus may include depositing a plurality of surface-enhanced spectroscopy (SES) elements onto respective tips of a plurality of nano-fingers, wherein the nano-fingers are arranged in sufficiently close proximities to each other to enable the tips of a group of adjacent nano-fingers to come into sufficiently close proximities to each other to enable the SES elements on the tips to trap fluorescent probe molecules that are to bind with target molecules when the nano-fingers are partially collapsed.

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: A method for forming a surface-enhanced fluorescence spectroscopy (SEFS) apparatus may include depositing a plurality of surface-enhanced spectroscopy (SES) elements onto respective tips of a plurality of nano-fingers, wherein the nano-fingers are arranged in sufficiently close proximities to each other to enable the tips of a group of adjacent nano-fingers to come into sufficiently close proximities to each other to enable the SES elements on the tips to trap fluorescent probe molecules that are to bind with target molecules when the nano-fingers are partially collapsed.

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: According to an example, methods for forming three-dimensional (3-D) nano-particle assemblies may include depositing surface-enhanced spectroscopy (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: 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: The present disclosure is drawn to chemical sensing devices and associated methods. In one example, a chemical sensing device can include a substrate; an elongated nanostructure having an attachment end and a free end opposite the attachment end, the attachment end affixed to the substrate and the free end including a metal; and a metal oxide coating applied to the elongated nanostructure. In one example, a functional group can be attached to the coating via a covalent bond.

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: 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 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: 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: Devices to detect a substance and methods of producing such a device are disclosed. An example device to detect a substance includes a housing defining a first chamber and a substrate coupled to the housing. The substrate includes nanostructures positioned within the first chamber. The nanostructures are to react to the substance when exposed thereto. The device includes a first heater positioned within the first chamber. The heater is to heat at least a portion of the substance to ready the device for analysis.

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: Devices to detect a substance and methods of producing such a device are disclosed. An example device to detect a substance includes an orifice plate defining a first chamber. A substrate is coupled to the orifice plate. The substrate includes nanostructures positioned within the first chamber. The nanostructures are to react to the substance when exposed thereto. A seal is to enclose at least a portion of the first chamber to protect the nanostructures from premature exposure.

Abstract: According to an example, methods for forming three-dimensional (3-D) nano-particle assemblies may include depositing surface-enhanced spectroscopy (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: The present disclosure is drawn to chemical sensing devices and associated methods. In one example, a chemical sensing device can include a substrate; an elongated nanostructure having an attachment end and a free end opposite the attachment end, the attachment end affixed to the substrate and the free end including a metal; and a metal oxide coating applied to the elongated nanostructure. In one example, a functional group can be attached to the coating via a covalent bond.

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: According to an example, an apparatus for performing spectroscopy includes a structure having an opening. The apparatus also includes a plurality of surface-enhanced Raman spectroscopy (SERS) elements positioned within the structure and a porous membrane covering the opening and the plurality of SERS elements. The porous membrane is to allow a predetermined analyte to reach the SERS elements while substantially preventing other analytes from reaching the SERS elements.