[14p-2D-1~19] 4.4 Opto-electronics

▲ [14p-2D-12] Sub-kHz linewidth lasers using integrated Si₃N₄ ring resonators

〇(DC)Daryl Spencer¹, John Bowers¹ (1.UC Santa Barbara)

キーワード：Lasers,Linewidth,Resonators

Frequency discriminators are attractive devices for reducing integrated laser linewidths for coherent communication systems and high purity microwave photonic systems. Standard diode lasers have MHz level linewidths and a few recent results have pushed this below 100 kHz. Typical on chip devices allow for a few cm of delay in a Mach Zehnder (MZI) configuration, but larger delays are needed for integrated devices. Here, we show a fully integrated Si₃N₄ ring resonator used as an optical discriminator with a sensitivity better than a 10 meter delay line interferometer. We utilize the Pound-Drever-Hall (PDH) technique to characterize the resonator bandwidth of 6.7 MHz (30 million loaded Q) and improve the linewidth of a state of the art commercial laser by locking to the waveguide coupled resonator. We measure a minimum frequency noise power spectral density of 30 Hz²/Hz at a 10 kHz offset.