Quantum dynamics of frustrated spin systems studied with high frequency susceptibility

我们研究了体系统的磁自旋动力学量子效应开始成为相关的低温。我们通过使用各种实验探针观察自旋弛豫来做到这一点。这些范围从中子和μ子，其中需要大型粒子加速器来产生这些粒子，然后可以绘制出基本属性，以及实验室设备。在卡迪夫，我们已经开发了一个高频磁化率探头系统，它可以在50 mK到400 K之间工作。你的博士学位将专注于研究这些技术的挫折材料，特别是我们看的材料出现的现象，例如，在自旋冰系统，我们已经调查了磁单极子的发生。这是从受抑基态的激发产生经历库仑相互作用的磁激发的地方，这个新颖的结果可以用来证明麦克斯韦方程组在电荷和磁荷之间具有直接对称性。在这个项目中，您将使用一系列实验技术，使用稀释冰箱和低温恒温器来探测自旋动力学的频率响应，然后根据我们领域的最新理解对结果进行建模。您将加入一个现有的小组（2个博士和一个PDRA），并发展一系列技能，包括实验物理，建模和项目规划，并有机会在国际会议上撰写论文和展示工作。在该项目的前6个月，将提供关于高频磁共振仪的培训，解释该领域理论和使用中央设施的课程，然后是24个月关于量子极限下自旋冰中单离子动力学的详细研究，以及12个月的手稿和论文写作。利用可用的，先进的设备，通过动态的每周会议促进将使一个充实的博士学位。

We investigate the magnetic spin dynamics of bulk systems as quantum effects start to become relevant at low temperature. We do this by looking at spin relaxation using a variety of experimental probes. These range from neutrons and muons, where large particle accelerators are required to produce these particles which can then map out the fundamental properties, and laboratory based equipment. At Cardiff we have developed a high frequency susceptibility probe system which can operate from 50 mK to 400 K. Your PhD would focus on investigating frustrated materials with these techniques, specifically we look at materials where emergent phenomena occur, for example in the spin ice systems we have investigated the occurrence of magnetic monopoles. This is where excitations out of the frustrated ground state create magnetic excitations that undergo a Coulomb interaction, this novel result can be used to demonstrate that Maxwells equations have a direct symmetry between electrical and magnetic charges. In this project you will use a range of experimental techniques using dilution fridges and cryostats to probe the frequency response of the spin dynamics and then model the results based on the latest understanding in our field. You will join an existing group (2 PHD and a PDRA) and develop a range of skills covering experimental physics, modelling and project planning with opportunities to write papers and present work at international conferences. In the first 6 months of the project, training on the high frequency susceptometer, courses explaining theory of the field and use of central facilities will be given followed by 24 months of detailed research on single ion dynamics in spin ice at the quantum limit, and 12 months manuscript and thesis writing. The use of available, cutting edge equipment facilitated by dynamic weekly meetings will enable a fulfilling PhD.