AIIIBV Molecular Beam Epitaxial structures and devices for photonics, nanoelectronics, spintronics and quantum computing.

技术革命带来了个人电脑、高速互联网、数码相机和平板显示器，这仅仅是商品领域，其根源可以直接追溯到人造材料超薄薄膜工程的进步。最高性能的电子设备，例如智能手机或卫星中使用的晶体管，以及支持沿着光纤网络进行超高速信息传输的半导体激光器等光子设备，都基于高度完美的半导体材料结晶多层，这些材料是使用外延工艺沉积的。在这些器件中，量子级联激光器（QCL）可能代表了外延技术的最大成就和固体能带理论和能带工程的最大胜利。这些激光器的有源区通常由一千多个不同的薄层组成--量子威尔斯和势垒--有些只有几个原子层厚。即使每个这样的量子势垒的有效厚度可以被控制在原子层的一小部分内，但是限制器件性能的是威尔斯和势垒之间的界面的质量。我们最近展示了世界上最高的工作温度200 K的QCL工作在非常困难的太赫兹光谱区。将它们的工作温度提高到240 K将使这些器件成为主流应用，很明显，界面结构需要在原子尺度上进行控制以实现这一目标。事实上，这种控制对许多其他量子器件至关重要，因为随着它们的尺寸缩小，界面区域开始主导它们的行为。了解和控制在原子尺度上的分子束外延界面形成的过程是拟议的研究计划的重点。获得的见解将用于提高THz QCL，量子热电子晶体管和量子结构的性能，这些结构被确定为革命性拓扑量子计算机的候选者。由此产生的知识产权，专有技术和高素质人才的稳定流动将利用加拿大高科技产业在全球市场上的强大地位。

The roots of the technological revolution which brought about personal computers, fast internet, digital cameras and flat panel displays-to mention just the commodity sector-can be traced directly to the advances in engineering of very thin films of artificial materials. The highest performance electronic devices, such as transistors used in smartphones or satellites, and photonic devices such as semiconductor lasers supporting the ultra-high speed information transfer along the optical fiber networks, are all based on highly perfect crystalline multilayers of semiconductor materials which are deposited using epitaxial processes. Of these devices the Quantum Cascade Lasers (QCLs) represent perhaps the greatest achievement of the epitaxial technology and the greatest triumph of the band theory of solids and band engineering. The active regions of these lasers are typically made of well over a thousand distinct thin layers - quantum wells and barriers - some just a couple of atomic layers thick. Even though the effective thickness of each such quantum barrier can be controlled to within a fraction of an atomic layer, it is the quality of interfaces between the wells and the barriers that limits the device performance. We recently demonstrated the world's record operating temperature of 200K for QCLs working in the very difficult THz spectral region. Increasing their operating temperature to 240K will bring these devices into the mainstream of applications and it is clear that interfacial structure needs to be controlled at atomic scale to achieve this goal. Such control is in fact of paramount importance to many other quantum devices, since as their size shrinks the interfacial regions start to dominate their behaviour. Understanding and controlling the processes of interface formation at atomic scale in Molecular Beam Epitaxy is the key focus of the proposed research program. Insights gained will be used to improve performance of THz QCLs, Quantum Hot Electron Transistors and quantum structures identified as candidates for revolutionary Topological Quantum Computers. The resulting intellectual properties, know-hows and the steady stream of highly qualified personnel will leverage the strong position of the Canadian high-tech industry in the global markets.