Magnetization switching, a promising direction of research within spintronics, has garnered significant attention in recent years due to its potential for revolutionizing information processing, computing, and data storage technologies in the post-CMOS era. Magnetization switching refers to the process of manipulating the orientation of
the magnetic moments of the free layer of a magnetic tunnel junction (MTJ), typically in the femtosecond (when using optical pulse) to nanosecond (when using electrical pulse) range. After switching the magnetization (the total time is referred to as write time), a small current pulse is passed through the material to read the resultant
magnetization state (which is called the read time). Ideally, both these timescales need to be improved /shortened in an energy-efficient fashion to compete with present-day semiconductor technology.
While spintronics-based magnetization switching has shown promising results, several challenges remain to be addressed. One of the main challenges is the need for a larger current density to achieve faster switching. On top of that the required current density increases non-linearly with faster switching speed. A large current density can
only be provided from a large transistor, which ultimately limits the size of the device. Hence improving the efficiency of spin transfer mechanisms is necessary. Research on new material development with better spintronic properties is required. The use of current pulses as external perturbation seems to be more feasible, at least in terms of
the device applications and the integration of the device with the conventional memory architecture. Generally, either spin-transfer-torque (SOT) or spin-orbit-torque-based (or a combination of both) devices are being studied for such applications. However, SOT switching is limited by the need for a symmetry-breaking in-plane magnetic field and larger effective device sizes. On the other hand, optical perturbation showed energy-efficient magnetization switching and the switching speed is three orders of magnitude faster. Recently, novel applications based on photonic waveguides have been proposed to use such devices in real-life applications. One should not only investigate optimizing the write time. An optimal MTJ stack is required to improve the temporal dynamics of such devices, which is mainly limited by the TMR ratio of the MTJ stack.
Researchers worldwide have made significant strides in developing experimental and simulation techniques, which provide valuable insights into the underlying physics and aid in the design and optimization of novel spintronics devices. However, as we discussed in the earlier section, a lot of challenges remain to be addressed. In this theme, we would like to receive articles on the following topics.
1) The use of new and unconventional materials in spintronics.
2) New results (both experiment and theory) on the improvement of writing and reading time, error rates, and device stability.
3) New developments in experimental and simulation techniques to study spintronics.
4) Study of magnetization switching (improvement of current density, energy efficiency, or switching speed) using different types of external perturbation.
5) The exploitation of ultrafast magnetization switching for nonconventional computing and signal processing.
Ultrafast magnetization switching holds tremendous potential for spintronics device applications, including memory, logic, and computing. The progress made in experimental techniques, coupled with the understanding of fundamental spin dynamics, has paved the way for exploring novel approaches to manipulate magnetization on ultrafast timescales. Continued research and collaborations in this field will contribute to unlocking the full potential of ultrafast magnetization switching, leading to transformative advancements in spintronics technology. Hence, I believe it is the perfect time to issue a special collection of articles based on the aforementioned theme which will be valuable for both the spintronics, microelectronics, and ultrafast magnetism community.
Keywords:
Spintronics, Spin-orbit torque (SOT) and spin-transfer torque (STT), Magnetic Tunnel Junction, Macro and Micromagnetic Simulations, Ultrafast Demagnetization, Helicity-independent All-optical Switching (HI-AOS)
Important Note:
All contributions to this Research Topic must be within the scope of the section and journal to which they are submitted, as defined in their mission statements. Frontiers reserves the right to guide an out-of-scope manuscript to a more suitable section or journal at any stage of peer review.
Magnetization switching, a promising direction of research within spintronics, has garnered significant attention in recent years due to its potential for revolutionizing information processing, computing, and data storage technologies in the post-CMOS era. Magnetization switching refers to the process of manipulating the orientation of
the magnetic moments of the free layer of a magnetic tunnel junction (MTJ), typically in the femtosecond (when using optical pulse) to nanosecond (when using electrical pulse) range. After switching the magnetization (the total time is referred to as write time), a small current pulse is passed through the material to read the resultant
magnetization state (which is called the read time). Ideally, both these timescales need to be improved /shortened in an energy-efficient fashion to compete with present-day semiconductor technology.
While spintronics-based magnetization switching has shown promising results, several challenges remain to be addressed. One of the main challenges is the need for a larger current density to achieve faster switching. On top of that the required current density increases non-linearly with faster switching speed. A large current density can
only be provided from a large transistor, which ultimately limits the size of the device. Hence improving the efficiency of spin transfer mechanisms is necessary. Research on new material development with better spintronic properties is required. The use of current pulses as external perturbation seems to be more feasible, at least in terms of
the device applications and the integration of the device with the conventional memory architecture. Generally, either spin-transfer-torque (SOT) or spin-orbit-torque-based (or a combination of both) devices are being studied for such applications. However, SOT switching is limited by the need for a symmetry-breaking in-plane magnetic field and larger effective device sizes. On the other hand, optical perturbation showed energy-efficient magnetization switching and the switching speed is three orders of magnitude faster. Recently, novel applications based on photonic waveguides have been proposed to use such devices in real-life applications. One should not only investigate optimizing the write time. An optimal MTJ stack is required to improve the temporal dynamics of such devices, which is mainly limited by the TMR ratio of the MTJ stack.
Researchers worldwide have made significant strides in developing experimental and simulation techniques, which provide valuable insights into the underlying physics and aid in the design and optimization of novel spintronics devices. However, as we discussed in the earlier section, a lot of challenges remain to be addressed. In this theme, we would like to receive articles on the following topics.
1) The use of new and unconventional materials in spintronics.
2) New results (both experiment and theory) on the improvement of writing and reading time, error rates, and device stability.
3) New developments in experimental and simulation techniques to study spintronics.
4) Study of magnetization switching (improvement of current density, energy efficiency, or switching speed) using different types of external perturbation.
5) The exploitation of ultrafast magnetization switching for nonconventional computing and signal processing.
Ultrafast magnetization switching holds tremendous potential for spintronics device applications, including memory, logic, and computing. The progress made in experimental techniques, coupled with the understanding of fundamental spin dynamics, has paved the way for exploring novel approaches to manipulate magnetization on ultrafast timescales. Continued research and collaborations in this field will contribute to unlocking the full potential of ultrafast magnetization switching, leading to transformative advancements in spintronics technology. Hence, I believe it is the perfect time to issue a special collection of articles based on the aforementioned theme which will be valuable for both the spintronics, microelectronics, and ultrafast magnetism community.
Keywords:
Spintronics, Spin-orbit torque (SOT) and spin-transfer torque (STT), Magnetic Tunnel Junction, Macro and Micromagnetic Simulations, Ultrafast Demagnetization, Helicity-independent All-optical Switching (HI-AOS)
Important Note:
All contributions to this Research Topic must be within the scope of the section and journal to which they are submitted, as defined in their mission statements. Frontiers reserves the right to guide an out-of-scope manuscript to a more suitable section or journal at any stage of peer review.