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A common technique for color center creation in wideband gap semiconductors employs ion implantation and a subsequent thermal annealing. In general, this annealing process is conducted in an vacuum oven. Here, we exploit the annealing based on femtosecond laser pulses. For that purpose, we implant fluorine ions at 54 keV and chlorine ions at 74 keV in diamond and perform micrometer precise annealing using focused femtosecond laser pulses at 800 ± (30) nm with different pulse numbers and repetition rates. In this way, we were able to create shallow spots with color centers of varying brightness. [ABSTRACT FROM AUTHOR]

The article focuses on demonstrating ultrafast spin-orbit torque (SOT)-induced coherent magnetization switching in a ferromagnet, which has significant implications for electrically controllable nonvolatile magnetic memories. Topics discussed include the use of an ultrafast electrical pulse to induce SOT, the role of thermal anisotropy torque in magnetization switching, and the potential for enhancing the writing speed of SOT magnetic random-access memory devices.

We offer a perspective on the prospects of ultrafast spintronics and opto-magnetism as a pathway to high-performance, energy-efficient, and non-volatile embedded memory in digital integrated circuit applications. Conventional spintronic devices, such as spin-transfer-torque magnetic-resistive random-access memory (STT-MRAM) and spin–orbit torque MRAM, are promising due to their non-volatility, energy-efficiency, and high endurance. STT-MRAMs are now entering into the commercial market; however, they are limited in write speed to the nanosecond timescale. Improvement in the write speed of spintronic devices can significantly increase their usefulness as viable alternatives to the existing CMOS-based devices. In this article, we discuss recent studies that advance the field of ultrafast spintronics and opto-magnetism. An optimized ferromagnet–ferrimagnet exchange-coupled magnetic stack, which can serve as the free layer of a magnetic tunnel junction (MTJ), can be optically switched in as fast as ∼3 ps. Integration of ultrafast magnetic switching of a similar stack into an MTJ device has enabled electrical readout of the switched state using a relatively larger tunneling magnetoresistance ratio. Purely electronic ultrafast spin–orbit torque induced switching of a ferromagnet has been demonstrated using ∼6 ps long charge current pulses. We conclude our Perspective by discussing some of the challenges that remain to be addressed to accelerate ultrafast spintronics technologies toward practical implementation in high-performance digital information processing systems. [ABSTRACT FROM AUTHOR]