Quantum Spin Lattices for Magnetic Silicon Devices

本研究的目的是开发和表征新的硅器件，即使由非磁性硅组成，也应该表现出各种磁性行为。最近的理论结果表明，在精细图案的二维晶格上，电子被限制在交叉位置；在较高的浓度下，额外的电子也占据间隙位置。多体量子理论预测，在这些不同的浓度下，由电子-电子相互作用引发的铁磁性、反铁磁性和其他几个相将会出现。只要改变控制电压，就可以在这些热力学稳定相之间“切换”。这种可控的“自旋晶格”在自旋电子器件中应该是有用的。该方法是在金属氧化物硅半导体晶体管的栅极上蚀刻晶格。理论和数值的努力将评估其新的电和磁特性。重要的是，当晶格特征缩小到10纳米以下时，这种现象应该扩大到室温。这个项目的一个更广泛的智力贡献是将最基本的量子物理学与先进的硅微电子学联系起来。当根据“摩尔定律”的晶体管进一步小型化变得不切实际时，成功的器件可能会取代晶体管，从而发挥重要的经济作用，潜在地在自旋电子学、量子计算和其他目前只能推测的应用中找到用途。该项目将培养研究生和本科生进行科学和工程研究，本科生准备样品并研究自旋晶格的晶体管特性。研究生将通过在新的“犹他州科学技术博物馆”创建一个互动展览来广泛传播这些知识。

The objective of this research is the development and characterization of new silicon devices that should exhibit a variety of magnetic behaviors at will - even though consisting of non-magnetic silicon. Recent theoretical results demonstrated that on a finely-patterned two-dimensional lattice, electrons are confined to intersection sites; at higher concentrations, additional electrons also occupy interstitial sites. Many-body quantum theory predicts that at these differing concentrations, Ferromagnetic, Antiferromagnetic, and several Other Phases will arise, triggered by electron-electron interactions. It should be possible to "switch" between these thermodynamically stable phases merely by changing a control voltage. Such controllable "Spin Lattices" should prove useful in spintronic devices. The approach is to etch lattices into the gate electrodes of silicon metal-oxide-semiconductor transistors. Theoretical and numerical efforts will evaluate their novel electrical and magnetic properties. Importantly, the phenomena should scale up to room temperature as lattice features scale down below 10 nm. A broader intellectual contribution of this project is the connection of the most basic quantum physics with advanced silicon microelectronics. Successful devices may play an important economic role by replacing transistors when further transistor miniaturization according to "Moore's Law" becomes impractical, potentially finding uses in spintronics, quantum computation, and other applications one can only conjecture at present. This project will train graduate and undergraduate students in scientific and engineering research, with undergraduate students preparing samples and investigating transistors properties for spin lattices. Graduate students will broadly disseminate this knowledge by creating an interactive exhibit in the new "Utah Museum of Science and Technology".