Thin-film Mach-Zehnder lithium niobate optical modulator on silicon substrates with VπL of 4 V·cm

Y-cut lithium niobate Mach-Zehnder optical modulators with record-low half-voltage length-product of 4 V·cm are demonstrated. A novel fabrication method that allows low-loss, high-index-contrast waveguides of lithium niobate on silicon substrate is used.