Electrical and optical control of single spins integrated in scalable semiconductor devices

Abstract

Spin defects in silicon carbide have exceptional electron spin coherence with a nearinfrared spin-photon interface in a material amenable to modern semiconductor fabrication. Leveraging these advantages, we successfully integrate highly coherent single neutral divacancy spins in commercially available p-i-n structures and fabricate diodes to modulate the local electrical environment of the defects. These devices enable deterministic charge state control and broad Stark shift tuning exceeding 850 GHz. Surprisingly, we show that charge depletion results in a narrowing of the optical linewidths by over 50 fold, approaching the lifetime limit. These results demonstrate a method for mitigating the ubiquitous problem of spectral diffusion in solid-state emitters by engineering the electrical environment while utilizing classical semiconductor devices to control scalable spin-based quantum systems.

Purcell Enhancement of a Single Silicon Carbide Color Center with Coherent Spin Control

“…Additionally, VV 0 ionization can be observed in our experiment under lower laser powers as a blinking behavior. Without a sufficiently strong 905 nm charge reset pulse, the VV 0 may be trapped in a non-radiative charge state for long periods of time, as has been observed in other work 41,42 . (2) (t) autocorrelation measurement of the nanobeam VV 0 , with a best fit (red) including the presence of a nonradiative state and a horizontal line (green) at g (2) = 0.5 indicating the upper threshold for a single emitter.…”

“…4a). This contrast level is significantly higher than the typical 10-15% observed for off-resonant Rabi oscillations 5 , but below the ~94-98% levels observed with resonant excitation 16,41,44 . This indicates that individual optical spin transitions are moderately selective, but still display a spectral overlap from the ~4-5 GHz PLE optical linewidths broadened from spectral diffusion.…”

Electrical charge state identification and control for the silicon vacancy in 4H-SiC

“…However, the overall low photon count rates plague emission from V Si in SiC, and optical signals from isolated defects are challenging to detect without resorting to nanofabricated waveguides, 11,22,23 or implementation into photonic crystal cavities. 24 Charge state conversion between the different V Si and V Si V C states in 4H-SiC 9,25 has been demonstrated by applying electric fields [26][27][28] or via laser excitation. [29][30][31] Unfortunately, the dark charge states under scrutiny remain largely unknown, and selective charge state population of V À…”

Relaxation dynamics of spin- 32 silicon vacancies in 4H -SiC

“…Due to the large breakdown voltages of SiC diodes and transistors, SiC devices are increasingly used in power electronic applications relevant to electric trains, cars and power transmission. As such rapid improvement in materials and device quality is to be expected, and there is growing interest in SiC for quantum devices [7][8][9][10][11].In this letter, we report room temperature optically detected magnetic resonance (ODMR) experiments on an ensemble of V2 silicon vacancies in 4H-SiC. By using a two microwave frequency setup, the +1/2 ↔ −1/2 transition can be detected optically [2] [12].…”

“…Due to the large breakdown voltages of SiC diodes and transistors, SiC devices are increasingly used in power electronic applications relevant to electric trains, cars and power transmission. As such rapid improvement in materials and device quality is to be expected, and there is growing interest in SiC for quantum devices [7][8][9][10][11].…”