Abstract: An elastic wave device includes a piezoelectric substrate, an IDT electrode located on the piezoelectric substrate, and a capacitive electrode that is located on the piezoelectric substrate and is connected in series with the IDT electrode. The capacitive electrode includes a plurality of capacitive electrode portions, each of which includes a pair of mutually interdigitated comb-shaped electrodes. The plurality of capacitive electrode portions are connected with each other in parallel. The plurality of capacitive electrode portions are arranged such that an intersecting width direction D1 of the capacitive electrode portions is inclined with respect to an intersecting width direction D2 of the IDT electrode. The plurality of capacitive electrode portions are arrayed in an elastic-wave propagating direction D3 of the IDT electrode.

Abstract: In an elastic wave apparatus, a first dielectric layer is laminated on a piezoelectric substrate. An electrode structure is provided at an interface between the first dielectric layer and the piezoelectric substrate. The electrode structure includes a first electrode structure of an elastic wave filter and a second electrode structure of elastic wave resonators. The elastic wave resonators are electrically connected to the elastic wave filter. An anti-resonant frequency at which the extreme impedance values of the elastic wave resonators are obtained is in a frequency band in which the higher-order mode spurious response of the elastic wave filter appears.