An acoustic resonator includes a piezoelectric thin film (PTF) disposed on a carrier substrate. The PTF confines a fundamental shear-horizontal (SH0) surface-acoustic wave (SAW) within the PTF. The acoustic resonator includes an input bus line coupled to an input source and a ground bus line coupled to a ground potential. The acoustic resonator includes a first grating reflector disposed at a first end of the PTF and coupled between the input bus line and the ground bus line. The acoustic resonator includes a second grating reflector disposed at a second end of the PTF and coupled between the input bus line and the ground bus line. The acoustic resonator includes interdigital transducers (IDTs) disposed between the first grating reflector and the second grating reflector. Each IDT includes an input electrode coupled to the input bus line, and a ground electrode coupled to the ground bus line.