Modern fabrication techniques have paved the way for many recent breakthroughs in electrically controlled semiconductor nanostructures with length scales on the order of tens of nanometers. Quantum dot devices containing one or several electrons have even been employed as quantum bits. Although these devices are highly adaptable, only a small number of quantum properties have been exploited to date as the basis for a quantum computer. However, the number of potential quantum variables grows quickly with the number of electrons. The aim of this project is to theoretically explore new multi-electron quantum dot configurations that may be particularly well suited for quantum computing. Experimental designs will be considered that contain multiple electrons per quantum dot, or multiple coupled dots. The goal is to identify quantum bits with desirable properties, in terms of control, speed or versatility. The operation of the new quantum bits will be characterized, and their interactions with the environment will be assessed, in order to optimize quantum operations. The identification of new high performance quantum bits will provide a blueprint for near-term experimental explorations, and for long-term, large-scale implementations.
The broader impacts will involve both researchers and members of the local community. The researchers will benefit from collaborations between scientists with different types of expertise. Graduate students will obtain a valuable range of interdisciplinary training and exposure to cutting edge research in a variety of fields. They will also obtain valuable experience presenting and explaining their research to coworkers with varying backgrounds. The broader impacts will be further enhanced by specific outreach activities in local schools and other venues.