Phase-Locked Rotation of Crystallized Non-neutral Plasmas by Rotating Electric Fields
Phase-Locked Rotation of Crystallized Non-neutral Plasmas by Rotating Electric Fields
复制标题
通过旋转电场实现结晶非中性等离子体的锁相旋转
DOI：
--
复制
发表时间：
1998
期刊：
影响因子：
--
通讯作者：
W. Itano
中科院分区：
文献类型：
--
作者：
X. Huang;J. Bollinger;T. Mitchell;W. Itano
具有单个电荷符号的大量粒子可以在Penning陷阱中被捕获和冷却[1,2]，该陷阱使用静电和磁场的组合来限制粒子。这些非中性等离子体围绕磁场轴的全球旋转是径向约束[3]所必需的。这种旋转的主动控制可以防止等离子体在静场误差和背景中性的环境阻力下自旋，这对许多实验都很重要，包括库仑晶体研究[4,5]、精密光谱学[6-8]、粒子和能量传输[9]的测量、反物质等离子体的捕获[10,11]和高度剥离离子[12]的存储。例如，在潘宁阱原子钟中，由于旋转速度引起的二阶多普勒（时间膨胀）位移可以通过将旋转稳定在特定频率[7]来最小化。激光束的辐射压力被用来改变等离子体的旋转频率[13,14]。然而，这种方法仅限于少数离子种类，其原子跃迁可以通过激光获得，并且由于激光功率，频率和指向波动而不精确。最近，旋转不对称（“旋转壁”）电场被用于对Mg施加扭矩
Large numbers of particles with a single sign ofcharge can be trapped and cooled in Penning traps [1,2],which use a combination of static electric and magneticfields for particle confinement. The global rotation ofthese non-neutral plasmas about the magnetic field axisis necessary for the radial confinement [3]. Activecontrol of this rotation prevents plasmas from spinningdown under the ambient drag from static field errorsand background neutrals, and is important for a numberof experiments including Coulomb crystal studies [4,5],precision spectroscopy [6–8], measurements of particleand energy transport [9], trapping of antimatter plasmas[10,11], and storage of highly stripped ions [12]. As anexample, the second-order Doppler (time dilation) shiftdue to rotational velocity in a Penning trap atomic clockcan be minimized by stabilizing the rotation at a particularfrequency [7]. Radiation pressure from laser beams hasbeen used to vary the plasma rotation frequency [13,14].However, this method is limited to the few ion specieswhose atomic transitions are accessible by a laser, and isnot precise due to laser power, frequency, and pointingfluctuations. Recently, rotating azimuthally asymmetric(“rotating wall”) electric fields have been used to applya torque on Mg