Coherent terahertz control of antiferromagnetic spin waves
Coherent terahertz control of antiferromagnetic spin waves
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DOI：
10.1038/nphoton.2010.259
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发表时间：
2011-01-01
期刊：
影响因子：
35
通讯作者：
Huber, Rupert
中科院分区：
文献类型：
--
作者：
Kampfrath, Tobias;Sell, Alexander;Huber, Rupert
电磁波谱中难以捉摸的太赫兹区域（1，2）中的超快电荷和自旋激发在凝聚态物质中起着关键作用（3-13）。自由空间太赫兹脉冲的电场为在飞秒时间尺度上操纵电荷的运动提供了直接的途径（6-9）。在这里，我们补充这一过程，表明强烈的太赫兹瞬态的磁分量，使自旋自由度的超快控制。单周期太赫兹脉冲在反铁磁NiO中以高达1 THz的频率打开和关闭相干自旋波。持续时间为8 fs的光探测脉冲直接在时域中跟随太赫兹诱导的磁动力学，并验证太赫兹场通过塞曼相互作用选择性地寻址自旋。这一概念提供了一种通用的超快手段来控制以前无法达到的电子基态磁激发。
Ultrafast charge and spin excitations in the elusive terahertz regime(1,2) of the electromagnetic spectrum play a pivotal role in condensed matter(3-13). The electric field of free-space terahertz pulses has provided a direct gateway to manipulating the motion of charges on the femtosecond timescale(6-9). Here, we complement this process by showing that the magnetic component of intense terahertz transients enables ultrafast control of the spin degree of freedom. Single-cycle terahertz pulses switch on and off coherent spin waves in antiferromagnetic NiO at frequencies as high as 1 THz. An optical probe pulse with a duration of 8 fs follows the terahertz-induced magnetic dynamics directly in the time domain and verifies that the terahertz field addresses spins selectively by means of the Zeeman interaction. This concept provides a universal ultrafast means to control previously inaccessible magnetic excitations in the electronic ground state.