标题： 非常规材料用于轻暗物质探测 显示英文标题

标题： Unconventional Materials for Light Dark Matter Detection

摘要： 我们建议使用几种非常规材料作为质量低于兆电子伏特尺度的暗物质探测器。 这些包括在电荷密度波相中具有低能等离子体的过渡金属二硫属化物TiSe$_2$，含有低能声学模态的Sr$_2$RuO$_4$，以及具有可调光学和声学等离子体频率的空穴掺杂金刚石。 我们对它们在非零动量下的损耗函数进行了第一性原理密度泛函理论计算，并确定了它们在轻暗物质参数空间中的探测范围。 我们表明，由于强烈的低能等离子体模式——每种材料的微观起源不同——基于这些材料的探测器在暗物质与电子的散射和吸收方面，其探测范围可能比现有提议高几个数量级。 这些材料的各向异性响应使得能够进行方向检测，使它们成为极其强大的探测器候选材料，这促使未来设备的设计和制造。 显示英文摘要

摘要： We propose the use of several unconventional materials as detectors for dark matter with mass beneath the MeV scale. These include the transition-metal dichalcogenide TiSe$_2$ hosting a low-energy plasmon in the charge-density-wave phase, Sr$_2$RuO$_4$ containing a low-energy acoustic demon mode, and hole-doped diamond with tunable optical and acoustic plasmon frequencies. We perform first-principles density functional theory computations of their loss functions at non-vanishing momenta and establish their reach into light dark matter parameter space. We show that due to intense low-energy plasmon modes -- of different microscopic origin in each -- the reach of detectors based on these materials could surpass existing proposals by several orders of magnitude for both dark matter scattering and absorption on electrons. The anisotropic response of these materials, which enables directional detection, renders them exceptionally strong detector candidates, motivating the design and fabrication of future devices.