Electrical manipulation of telecom color centers in silicon.

Silicon color centers have recently emerged as promising candidates for commercial quantum technology, yet their interaction with electric fields has yet to be investigated. In this paper, we demonstrate electrical manipulation of telecom silicon color centers by implementing novel lateral electrical diodes with an integrated G center ensemble in a commercial silicon on insulator wafer. The ensemble optical response is characterized under application of a reverse-biased DC electric field, observing both 100% modulation of fluorescence signal, and wavelength redshift of approximately 1.24 ± 0.08 GHz/V above a threshold voltage. Finally, we use G center fluorescence to directly image the electric field distribution within the devices, obtaining insight into the spatial and voltage-dependent variation of the junction depletion region and the associated mediating effects on the ensemble. Strong correlation between emitter-field coupling and generated photocurrent is observed. Our demonstration enables electrical control and stabilization of semiconductor quantum emitters.

Laser writing of spin defects in nanophotonic cavities.

High-yield engineering and characterization of cavity-emitter coupling is an outstanding challenge in developing scalable quantum network nodes. Ex situ defect formation systems prevent real-time analysis, and previous in situ methods are limited to bulk substrates or require further processing to improve the emitter properties1-6. Here we demonstrate the direct laser writing of cavity-integrated spin defects using a nanosecond pulsed above-bandgap laser. Photonic crystal cavities in 4H-silicon carbide serve as a nanoscope monitoring silicon-monovacancy defect formation within the approximately 200 nm3 cavity-mode volume. We observe spin resonance, cavity-integrated photoluminescence and excited-state lifetimes consistent with conventional defect formation methods, without the need for post-irradiation thermal annealing. We further find an exponential reduction in excited-state lifetime at fluences approaching the cavity amorphization threshold and show the single-shot annealing of intrinsic background defects at silicon-monovacancy formation sites. This real-time in situ method of localized defect formation, paired with cavity-integrated defect spins, is necessary towards engineering cavity-emitter coupling for quantum networking.