Fig. 2: Transmitter characterization and performance.

a, An illustration of the transmitter experimental test setup showing a single wavelength laser channel modulated by the transmitter and measured on an oscilloscope. b, The transmitter cell circuit schematic. c, An optical spectrum of the four-channel transmitter bus. d, A resonance shift of a representative microdisk as a function of reverse-bias voltage applied to the vertical p–n junction. e, The transmitted signal ER (power of ‘1’ bit divided by power of ‘0’ bit), IL (power of ‘1’ bit divided by power before the modulator) and normalized OMA (normalized power of ‘1’ bit minus power of ‘0’ bit) with a 1.5 V driver voltage. f, The ER and IL at maximum OMA for a range of driver voltages. g, Measured energy consumption of the transmitter array for a range of driver voltages and a \(\frac{1}{4}\) CV² fit, where C is the capacitance charged by the driver voltage V. h, A BER measurement of the modulated signal input to a commercial receiver at 1, 1.25 and 1.5 V driver voltages; the received power is the average signal power at the commercial receiver. i, Eye diagrams for all 80 modulators on the photonic chip at 10 Gb s⁻¹ per modulator and 1 dBm input laser power.