Developing silicon carbide for quantum spintronics

Abstract

In current long-distance communications, classical information carried by large numbers of particles is intrinsically robust to some transmission losses but can, therefore, be eavesdropped without notice. On the other hand, quantum communications can provide provable privacy and could make use of entanglement swapping via quantum repeaters to mitigate transmission losses. To this end, considerable effort has been spent over the last few decades toward developing quantum repeaters that combine long-lived quantum memories with a source of indistinguishable single photons. Multiple candidate optical spin qubits in the solid state, including quantum dots, rare-earth ions, and color centers in diamond and silicon carbide (SiC), have been developed. In this perspective, we give a brief overview on recent advances in developing optically active spin qubits in SiC and discuss challenges in applications for quantum repeaters and possible solutions. In view of the development of different material platforms, the perspective of SiC spin qubits in scalable quantum networks is discussed.

Photoluminescence line shapes for color centers in silicon carbide from density functional theory calculations

“…During the past decade, improvements in the fabrication techniques of silicon carbide (SiC), a material with a wide electronic band gap of 3.2 eV [1], have made it possible to produce high-quality samples [2,3] with control over types and concentrations of color centers in this system, making SiC attractive for applications in nanophotonics, electronics, and spintronics [4][5][6]. These centers can potentially be used as single-photon sources and spin-photon interfaces [7][8][9][10][11][12][13], and thus they could play a central role in future quantum technologies [14][15][16][17]. Nowadays, it is also possible to prepare SiC with largely isolated color centers, which allows investigations of the properties of specific types of color centers [18,19].…”

“…While purely electronic transitions give rise to the so-called ZPLs, transitions that involve phonon creation or annihilation lead to the so-called phonon sideband (PSB), which is located at lower (higher) energies than the ZPL in photon emission (absorption) spectra. From the ZPL and PSB, one can extract the Huang-Rhys factor (HRF) and the Debye-Waller factor (DWF) [44], which are important 2469-9950/2021/103(12)/125203 (9) 125203-1 ©2021 American Physical Society parameters to assess the suitability of defects for quantum applications. The DWF describes the relative ratio of light emitted in the ZPL relative to the total emitted light, and the HRF describes the average number of phonons involved in the emission.…”

Manipulating Single‐Photon Emission from Point Defects in Diamond and Silicon Carbide

“…The quantum compatible charge state for each defect type is highlighted by the colored regions. SPE material platforms, [33] SiC for quantum applications, [34,35] diamond [36][37][38] and SiC [14] nanophotonics, and density functional theory (DFT) calculations to study point defects for quantum technology (QT). [39,40] The report is organized as follows.…”

Spin Polarization and Magnetic Moment in Silicon Carbide Grown by the Method of Coordinated Substitution of Atoms

“…In recent years, much attention has been paid to the creation of solid-state devices, the operations of which are based not on the charge but the spin of charged particles; therefore, the development of new materials with the property of spin polarization is a very important task [ 1 , 2 , 3 ]. In addition, it is desirable that these materials combine well with the standard materials of microelectronics, such as silicon Si, silicon carbide SiC, or III-V semiconductor compounds.…”