Quantum optimal control of semiconductor nanostructures

Quantum information processing is a new research arena that holds a lot of promise. Its key elements are arrays of quantum bits or qubits for the storage of the quantum information, and quantum gates through which the quantum information can be processed. Such quantum information processing could --if implemented successfully-- eventually outperform classical information technology. Yet, the hardware requirements and the degree of controllability are tremendous. The main challenge lies in the identification of a quantum memory which is efficiently proteced from its environment and thus retains its quantum properties sufficiently long. At this point one meets with the realm of semiconductor nano science and technology, where the performance of the next generation of devices is expected to be governed by the laws of quantum mechanics. Here two questions are of central importance: can one identify semiconductor systems which can be used as viable quantum memories?, and what is the the best way to process quantum information? The goal of this project is to theoretically investigate the prospect of success for quantum control applications in prototypical semiconductor nanostructures (artificial atoms). We will pursue two different directions, namely simulation of nanostructures and optimal control theory -- a mathematical device suited for the systematic search of `optimal` quantum gating or quantum control. We will develop fast and efficient computer algorithms suited for quantum optimal control applications of open quantum systems. The work will cover both aspects of numerical mathematics and of theoretical physics, and will be carried out in a joint interdisciplinary collaboration between experts in the respective fields. The expected impact of this work is in the field of simulation and optimization of quantum control in low- dimensional open quantum systems. We will identify the necessary conditions under which quantum systems can be adequately controlled by means of external fields. A number of fast algorithms and general software tools will be developed, which will be also beneficial to the broader communities of nanoscience and quantum information researchers.

Quantum information processing is a new research arena that holds a lot of promise. Its key elements are arrays of quantum bits or qubits for the storage of the quantum information, and quantum gates through which the quantum information can be processed. Such quantum information processing could --if implemented successfully-- eventually outperform classical information technology. Yet, the hardware requirements and the degree of controllability are tremendous. The main challenge lies in the identification of a quantum memory which is efficiently proteced from its environment and thus retains its quantum properties sufficiently long. At this point one meets with the realm of semiconductor nano science and technology, where the performance of the next generation of devices is expected to be governed by the laws of quantum mechanics. Here two questions are of central importance: can one identify semiconductor systems which can be used as viable quantum memories?, and what is the the best way to process quantum information? The goal of this project is to theoretically investigate the prospect of success for quantum control applications in prototypical semiconductor nanostructures (artificial atoms). We will pursue two different directions, namely simulation of nanostructures and optimal control theory -- a mathematical device suited for the systematic search of `optimal` quantum gating or quantum control. We will develop fast and efficient computer algorithms suited for quantum optimal control applications of open quantum systems. The work will cover both aspects of numerical mathematics and of theoretical physics, and will be carried out in a joint interdisciplinary collaboration between experts in the respective fields. The expected impact of this work is in the field of simulation and optimization of quantum control in low- dimensional open quantum systems. We will identify the necessary conditions under which quantum systems can be adequately controlled by means of external fields. A number of fast algorithms and general software tools will be developed, which will be also beneficial to the broader communities of nanoscience and quantum information researchers.