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Updated: Jun 29, 2025

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Magnetic Tweezers for the Measurement of Twist and Torque
Published on: May 19, 2014
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磁道连接随机数发生器应用于由旋转轨道扭矩驱动的动态调节的概率树.
Andrew Maicke1, Jared Arzate1, Samuel Liu1
1University of Texas at Austin, Austin, TX, United States of America.
Nanotechnology
|April 5, 2024
概括
垂直磁道连接 (pMTJ) 真正随机数发生器可以节省大量的能源. 这些设备可以从各种概率分布中取样数字,在速度和能源效率方面超过CMOS和memristorRNG.
科学领域:
- 这就是Spintronics.
- 随机数生成器 随机数生成器
背景情况:
- 传统的CMOS伪随机数生成器 (RNG) 是能源密集型的.
- 垂直磁道连接 (pMTJs) 为RNG提供了低功耗的替代方案.
研究的目的:
- 为了从数值上研究由旋转轨道扭矩驱动的pMTJ,从任意概率分布生成随机数.
- 评估设备对设备的变化对RNG性能的影响.
主要方法:
- 使用一个Landau-Lifshitz-Gilbert方程解法器.
- 采用可调节的概率树来偏向pMTJ放松事件 ("硬币翻转") 使用旋转转移扭矩.
- 基于制造数据模拟单个理想的pMTJ和变化的pMTJ热稳定性.
主要成果:
- 从使用单个pMTJ的指数分布中成功生成整数样本.
- 发现,在使用"桶"设备时,设备变异的平均值会变化,从而使不可知随机数生成成为可能.
- 通过使用均和指数分布的数字,证明了精确的粒子运输蒙特卡洛计算.
- 与CMOS和memristor RNG相比,pMTJ RNG的比特生成速度更快,能耗明显降低.
结论:
- 基于pMTJ的RNG是对现有技术的高能效和快速替代方案.
- 拟议的概率树方法有效地从任意分布中取样,即使有设备变化.
- 设备变化具有可管理的影响,特别是当它们在多个设备上聚合时.
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