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- Navin Khaneja, Roger Brockett, Steffen J Glaser
- 2001

In this paper, we study the design of pulse sequences for NMR spectroscopy as a problem of time optimal control of the unitary propagator. Radio frequency pulses are used in coherent spectroscopy to implement a unitary transfer of state. Pulse sequences that accomplish a desired transfer should be as short as possible in order to minimize the effects of… (More)

- Navin Khaneja, Burkhard Luy, Steffen J Glaser
- Proceedings of the National Academy of Sciences…
- 2003

Relaxation effects impose fundamental limitations on our ability to coherently control quantum mechanical phenomena. In this article, we use principles of optimal control theory to establish physical limits on how closely a quantum mechanical system can be steered to a desired target state in the presence of relaxation. In particular, we explicitly compute… (More)

- Navin Khaneja, Steffen J Glaser, Roger Brockett
- 2002

Radio-frequency pulses are used in nuclear-magnetic-resonance spectroscopy to produce unitary transfer of states. Pulse sequences that accomplish a desired transfer should be as short as possible in order to minimize the effects of relaxation, and to optimize the sensitivity of the experiments. Many coherence-transfer experiments in NMR, involving a network… (More)

- Navin Khaneja, Timo Reiss, Burkhard Luy, Steffen J Glaser
- Journal of magnetic resonance (San Diego, Calif…
- 2003

Experiments in coherent spectroscopy correspond to control of quantum mechanical ensembles guiding them from initial to final target states. The control inputs (pulse sequences) that accomplish these transformations should be designed to minimize the effects of relaxation and to optimize the sensitivity of the experiments. For example in nuclear magnetic… (More)

In this paper, we develop methods for optimal manipulation of coupled spin dynamics in the presence of relaxation. These methods are used to compute analytical bounds for the optimal efficiency of coherence transfer between coupled nuclear spins in presence of longitudinal and transverse relaxation. We derive relaxation optimized pulse sequences which… (More)

Quantum control plays a key role in quantum technology, e.g. for steering quantum hardware systems, spectrometers or supercon-ducting solid-state devices. In terms of computation, quantum systems provide a unique potential for coherent parallelisation that may exponentially speed up algorithms as in Shor's prime factorisation. Translating quantum software… (More)

The objective of this article is to introduce the tools to analyze the contrast imaging problem in Nuclear Magnetic Resonance. Optimal trajecto-ries can be selected among extremal solutions of the Pontryagin Maximum Principle applied to this Mayer type optimal problem. Such trajectories are associated to the question of extremizing the transfer time. Hence… (More)

- Navin Khaneja, Jr-Shin Li, Cindie Kehlet, Burkhard Luy, Steffen J Glaser
- Proceedings of the National Academy of Sciences…
- 2004

Many applications of magnetic resonance are limited by rapid loss of spin coherence caused by large transverse relaxation rates. In NMR of large proteins, increased relaxation losses lead to poor sensitivity of experiments and increased measurement time. In this article, we develop broadband relaxation-optimized pulse sequences that approach fundamental… (More)

- Florian Wiesinger, Eliane Weidl, Marion I Menzel, Martin A Janich, Oleksandr Khegai, Steffen J Glaser +3 others
- Magnetic resonance in medicine
- 2012

Metabolic imaging with hyperpolarized [1-(13)C]pyruvate offers the unique opportunity for a minimally invasive detection of cellular metabolism. Efficient and robust acquisition and reconstruction techniques are required for capturing the wealth of information present for the limited duration of the hyperpolarized state (~1 min). In this study, the… (More)

Experiments in coherent spectroscopy correspond to control of quantum mechanical ensembles guiding them from initial to final target states by unitary transformations. The control inputs ͑pulse sequences͒ that accomplish these unitary transformations should take as little time as possible so as to minimize the effects of relaxation and to optimize the… (More)