Chemical control of spin-phonon coupling and magnetisation dynamics

自旋声子耦合和磁化动力学的化学控制

• 批准号: 2105188
• 金额: --
• 依托单位: University of Manchester
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2018
• 资助国家: 英国
• 起止时间: 2018 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2105188
• 关键词: Chemical; control; spin; phonon; coupling

Manufacturing new technologies with bottom-up approaches could lead to reductions in device size with increased energy efficiency. An example is the use of molecules for binary data storage, which requires data to be non-volatile at temperatures achievable with economical cooling requirements; a common benchmark is the temperature of liquid nitrogen (77 K). We have recently made a step-change by raising the temperature at which molecular memory can be observed from 14 K to 60 K in a dysprosocenium single-molecule magnet (SMM) (Goodwin, Ortu, Reta, Chilton and Mills, Nature, 2017, 548, 439). Interaction of the molecular electronic spin with its environment (spin-phonon coupling) is a critically limiting feature for SMM performance, as it leads to magnetic relaxation and the loss of magnetic information. To realise molecule-based high-density data storage, we must control the spin-phonon coupling.We recently developed a computational method for calculating spin-phonon coupling and employed it to show that magnetic relaxation in dysprosocenium at high temperatures is due to localised molecular vibrations, with four vibrational modes being particularly important. This project will employ our computational method to develop general strategies for controlling the spin-phonon coupling in SMMs, leading to targeted design of SMMs displaying magnetic memory at higher temperatures, and thus delivering technologically viable candidates for molecule-based high-density data storage.The objectives are:(i) to understand how molecular structure influences vibrational spectrum (ii) to understand how spin-phonon coupling can be modulated by molecular structure(iii) to determine design criteria for improved SMMsThese objectives will be achieved by:(i) employing density-functional theory calculations on hypothetical molecules to catalogue structure-vibration relationship(ii) employing our spin-phonon coupling method to determine how magnetic relaxation is influenced by vibrational profileThis project is directly relevant to the EPSRC "Physical Sciences" and "Quantum Technologies" research themes, specifically to the "Physics grand challenge(s)" of "Quantum Physics for New Quantum Technologies" and "Nanoscale Design of Functional Materials", and the "Chemical sciences and engineering grand challenge" of "Directed Assembly of Extended Structures with Targeted Properties".

以自下而上的方法制造新技术可能会随着能源效率的提高而导致设备尺寸减少。一个例子是将分子用于二进制数据存储，这要求在经济冷却要求下可达到的温度下进行非易失性；一个常见的基准是液氮的温度（77 K）。最近，我们通过提高温度来改变了逐步变化，在该温度下，在失臭症单分子磁铁（SMM）中可以观察到分子记忆的温度（goodwin，ortu，ortu，reta，chilton and Mills，nature，2017，548，439）。分子电子自旋与其环境的相互作用（自旋 - 音波耦合）是SMM性能的严重限制特征，因为它会导致磁性松弛和磁性信息的损失。为了实现基于分子的高密度数据存储，我们必须控制自旋光子耦合。我们最近开发了一种计算方法，用于计算自旋光子耦合，并采用它来表明，高温下脱氧化症中的磁性松弛是由于局部分子振动所致，其四个振动模式特别重要。该项目将采用我们的计算方法来制定一般策略来控制SMM中的自旋载体耦合，从而导致SMM的有针对性设计在较高的温度下显示磁性记忆，从而为基于分子的高密度数据存储提供技术可行的候选物。结构（iii）确定改善SMMS的设计标准，将通过以下方式实现：（i）对假设分子的密度官能理论计算进行编目结构振动关系（II）采用我们的自旋 - 光量耦合方法来确定磁性量的振动量化技术与振动量的影响与Epsim Intormention与Epsim Intoligation and Epsim Intipies Intimantimant Impsim and Epsim Intimantim and Epsim Intimantim主题，特别是针对“新量子技术的量子物理学”和“功能材料的纳米级设计”的“物理大挑战”，以及“有针对性特性的扩展结构的定向组装”的“化学科学与工程大挑战”。