Electrically Tunable Quantum Platform Using Spin Defects In SiC Heterostructures

SUMMARY

• Integration of quantum spins into classical electronic devices has been a major challenge. However, the ability to do so would limit spectral noise and line width broadening of emissions from solid state devices, resulting in improved device performance. The divacancy in Silicon Carbide is a recently developed defect spin qubit displaying many attractive properties that could address these challenges. However, these defects have suffered from relatively broad optical lines, charge instability and relatively small Stark shifts. This invention addresses these issues through a semiconductor structure embedded with highly coherent single neutral divacancy spin defects having near-infrared transitions with a narrow emission spectrum demonstrating a method for mitigating spectral diffusion in solid-state emitters. The inventors leverage mature silicon carbide semiconductor fabrication techniques to p-i-n heterostructures with tunable charge and electrical field environment enabling narrowing optical lines, stabilizing charge states and creating large Stark shifts. These heterostructures constitute a testbed for studying the photoionization of divalent defects, resulting in a charge reset scheme that allows for full optical control of the defect. The combination of the effects suggest doped silicon carbide heterostructures are a powerful quantum platform for enabling narrow optical lines, long spin coherence, high fidelity control, electrical tunability and efficient charge repumping. This platform also opens unique avenues for spin-to-charge conversion, single-shot readout, electrically driven single photon emission, electrical control of spin and the integration of defects into new device geometries. More broadly, the invention points towards a general method for reducing spectral diffusion in solid state emitters, while utilizing the unique properties of p-i-n devices to create integrated defect based systems with ideal properties for quantum technologies. Figure Schematic of device geometry for isolation of single, addressable, controllable, high coherence double vacancies in a commercially grown heterostructure.

• This invention addresses these issues through a semiconductor structure embedded with highly coherent single neutral divacancy spin defects having near-infrared transitions with a narrow emission spectrum demonstrating a method for mitigating spectral diffusion in solid-state emitters.

• The inventors leverage mature silicon carbide semiconductor fabrication techniques to p-i-n heterostructures with tunable charge and electrical field environment enabling narrowing optical lines, stabilizing charge states and creating large Stark shifts. These heterostructures constitute a testbed for studying the photoionization of divalent defects, resulting in a charge reset scheme that allows for full optical control of the defect. The combination of the effects suggest doped silicon carbide heterostructures are a powerful quantum platform for enabling narrow optical lines, long spin coherence, high fidelity control, electrical tunability and efficient charge repumping. This platform also opens unique avenues for spin-to-charge conversion, single-shot readout, electrically driven single photon emission, electrical control of spin and the integration of defects into new device geometries.

• More broadly, the invention points towards a general method for reducing spectral diffusion in solid state emitters, while utilizing the unique properties of p-i-n devices to create integrated defect based systems with ideal properties for quantum technologies.

FIGURE

ADVANTAGES

ADVANTAGES

• Tunable charge and electrical field environment
• Narrow optical emission lines
• Stabilized charge states
• Large Stark shifts

APPLICATIONS

• Optoelectronic devices
• Quantum computing
•  Integrated circuits

February 10, 2022

Proof of concept

Patent Pending

Licensing,Co-development

David Awschalom