The precessional switching mechanism has governed the magnetic switching in magnetic tunnel junctions (MTJs) in the sub-nanosecond range, which exponentially increases the switching current density of magnetic random access memory (MRAM). Thus, there needs to be an alternative switching mechanism with much higher energy efficiency to bring down the switching current density significantly and make the MRAM compatible with high-speed L1/2-static random access memory (SRAM) at sub-nanosecond range. Using the recent discovered external electric field ( E-field) tunable Ruderman-Kittel-Kasuya-Yosida (RKKY) phenomena in a synthetic ferrimagnet (E-SFi), we propose a totally different Chrysanthemum-like switching mechanism to realize a low-energy picosecond writing MRAM design, which breaks the precessional switching mechanism at picosecond region. And our results show that the critical switching current density can be significantly reduced by one order of magnitude compared to that of a conventional MTJ design down to 100 ps. In addition, we study the robustness of the asynchronous conditions between the charge current pulse and the E-field pulse for its practical applications.

中文翻译：

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利用电场调谐 RKKY 效应实现合成亚铁磁自由层的低能量皮秒磁开关


进动切换机制控制了亚纳秒范围内磁性隧道结 (MTJ) 的磁性切换，从而以指数方式增加了磁性随机存取存储器 (MRAM) 的切换电流密度。因此，需要一种具有更高能效的替代开关机制，以显着降低开关电流密度，并使 MRAM 与亚纳秒范围内的高速 L1/2 静态随机存取存储器 (SRAM) 兼容。利用最近在合成亚铁磁体（E-SFi）中发现的外部电场（E场）可调谐Ruderman-Kittel-Kasuya-Yosida（RKKY）现象，我们提出了一种完全不同的类菊花开关机制，以实现低能量皮秒写入MRAM设计，打破了皮秒区域的进动切换机制。我们的结果表明，与传统 MTJ 设计相比，临界开关电流密度可显着降低一个数量级，低至 100 ps。此外，我们还研究了充电电流脉冲和电场脉冲之间的异步条件的鲁棒性，以供其实际应用。