It is control that turns scientific knowledge into useful technology: in physics and engineering it provides a systematic way for driving a dynamical system from a given initial state into a desired target state with minimized expenditure of energy and resources As one of the cornerstones for enabling quantum technologies, optimal quantum control keeps evolving and expanding into areas as diverse as quantum-enhanced sensing, manipulation of single spins, photons, or atoms, optical spectroscopy, photochemistry, magnetic resonance (spectroscopy as well as medical imaging), quantum information processing and quantum simulation In this communication, state-of-the-art quantum control techniques are reviewed and put into perspective by a consortium of experts in optimal control theory and applications to spectroscopy, imaging, as well as quantum dynamics of closed and open systems We address key challenges and sketch a roadmap for future developments

/pdf/training-schrodinger-s-cat-quantum-optimal-control-ra2pns71lh.pdf

Training Schrödinger’s cat: quantum optimal control

It is control that turns scientific knowledge into useful technology: in physics and engineering it provides a systematic way for driving a system from a given initial state into a desired target state with minimized expenditure of energy and resources -- as famously applied in the Apollo programme. As one of the cornerstones for enabling quantum technologies, optimal quantum control keeps evolving and expanding into areas as diverse as quantum-enhanced sensing, manipulation of single spins, photons, or atoms, optical spectroscopy, photochemistry, magnetic resonance (spectroscopy as well as medical imaging), quantum information processing and quantum simulation. --- Here state-of-the-art quantum control techniques are reviewed and put into perspective by a consortium uniting expertise in optimal control theory and applications to spectroscopy, imaging, quantum dynamics of closed and open systems. We address key challenges and sketch a roadmap to future developments.

/pdf/training-schr-odinger-s-cat-quantum-optimal-control-16o299lhlz.pdf

Training Schr\"odinger's cat: quantum optimal control

A family of new iteration methods is presented for designing quantum optimal controls to manipulate the transition probability Theoretical analysis shows that these new methods exhibit quadratic and monotonic convergence Numerical calculations verify that for these new methods, within very few steps, the optimized objective functional comes close to its convergent limit

Rapidly convergent iteration methods for quantum optimal control of population

A new iteration method is presented for achieving quantum optimal control over the expectation value of a positive definite operator. Theoretical analysis shows that this new algorithm exhibits quadratic and monotonic convergence. Numerical calculations verify that for this new algorithm, within a few steps, the optimized objective functional comes close to its converged limit.

A rapid monotonically convergent iteration algorithm for quantum optimal control over the expectation value of a positive definite operator

This Centennial Issue of The Journal of Physical Chemistry marks not only its achievements since birth in 1896 but also an era of great scientific contributions to the field of chemical dynamics. Pioneering work in the studies of molecular reaction dynamics, which continued over a century, led to new methods of experimentation and to new concepts. Letokhov [1] has identified “three waves” in the development of molecular dynamics, depending on the time scale. In this account we focus on the third wave characterized by femtosecond time resolution. Chemistry occurring on this time scale, femtochemistry, is microscopic, on the length scale of a bond, allowing us to address the nature of transition states and their control, a subject also started in the first part of this century.

Jozsef Somloi

Papers

Controlled dissociation of I2 via optical transitions between the X and B electronic states

Controlled Dissociation of HgI2 via Optical Transitions between Electronic States