According to an example, an apparatus for performing spectroscopy includes a substrate on which a plurality of surface-enhanced spectroscopy (SES) elements are positioned substantially along a first plane. The apparatus also includes a first electrode positioned adjacent to the plurality of SES elements substantially along the first plane and a second electrode positioned adjacent to the plurality of SES elements substantially along the first plane and on a side of the plurality of SES elements that is opposite the first electrode. The first electrode and the second electrode are to generate an electric field around the plurality of SES elements when voltages are applied through the first electrode and the second electrode.