标题： 磁性稀释自旋冰中的偶极效应 显示英文标题

标题： Dipolar effects on the behavior of magnetically diluted spin-ice

摘要： 在本工作中，我们研究了稀释自旋冰系统的磁行为，其中磁矩在不同浓度下被随机移除。我们关注的是长程偶极相互作用的影响（通常在这些系统中被自屏蔽所掩盖），通过稀释使其显现出来。我们的初步重点是在零场下冷却至低温后达到的配置，并扫描杂质的整个密度范围。我们观察到，缺失的磁矩引发了一种局部的磁荷有序。接下来，使用蒙特卡洛模拟，我们研究了在[111]晶体学方向施加磁场时磁化的行为。包含偶极相互作用能够解释之前实验结果中的主要特征。使用哑铃模型，其中磁矩被表示为一对相反电荷的磁单极子，我们能够理解随着掺杂增加这些曲线的定性行为。此外，我们利用这个框架计算了纯样品中观察到相变对应的临界场以及在非常低掺杂时出现的特征场。 显示英文摘要

摘要： In this work, we explore the magnetic behavior of diluted spin-ice systems, where magnetic moments are randomly removed at various concentrations. We concentrate on features in which the effect of long range dipolar interactions (usually masked by self-screening in these systems) is made visible by dilution. Our initial focus is on the configurations reached after cooling to low temperatures at zero-field, sweeping the whole density range of impurities. We observe that the missing magnetic moments induce a certain type of local, magnetic charge order. Next, using Monte Carlo simulations, we examine the behavior of the magnetization under an applied magnetic field in the [111] crystallographic direction. The inclusion of dipolar interactions allows to account for the main features observed in previous experimental results. Using the dumbbell model, where magnetic moments are represented as pairs of oppositely charged magnetic monopoles, we are able to understand the qualitative behavior of these curves as we increase doping. Additionally, we use this framework to calculate the critical fields corresponding to the phase transition observed in pure samples, and the characteristic fields appearing at very low doping.