On a microscopic scale molecules are complex quantum systems that provide a variety of properties with potential applications in the fields of data storage and information processing. Molecular vibrations are the motor in many of these processes and define the relevant time scale in the femto- to picosecond range. Efficient control of the vibrational motion can be obtained with optimally shaped femtosecond laser pulses. We apply optimal control theory to calculate the driving laser fields for a given control objective. To obtain a flexible and reliable tool which delivers robust laser fields, the control algorithms were extended to include multiple target states, laboratory constraints and the momentum of the target wave packet [1,2]. Two different applications for molecular devices will be presented. In the first example control strategies for molecular switches in donorbridge- acceptor systems driven via ultrafast reactions will be discussed [2]. The selected molecules are bistable aromatic compounds, which can be optically switched from one stable isomer to the other, allowing or preventing energy transfer. The second example is the implementation of universal quantum gates and quantum algorithms operating on molecular vibrational qubits [1,3,4].
[1] C. M. Tesch, R. de Vivie-Riedle, Phys. Rev. Lett. 89 (2002) 157901.
[2] D. Geppert, L. Seyfarth, and R. de Vivie-Riedle, App. Phys. B 79 (2004) 987-992.
[3] C. Tesch and R. de Vivie-Riedle, J. Chem. Phys. 121 (2004) 12158-12168.
[4] U. Troppmann and R. de Vivie-Riedle, J. Chem. Phys. 122 (2005) 154105.
On a microscopic scale molecules are complex quantum systems that provide a variety of properties with potential applications in the fields of data storage and information processing. Molecular vibrations are the motor in many of these processes and define the relevant time scale in the femto- to picosecond range. Efficient control of the vibrational motion can be obtained with optimally shaped femtosecond laser pulses. We apply optimal control theory to calculate the driving laser fields for a given control objective. To obtain a flexible and reliable tool which delivers robust laser fields, the control algorithms were extended to include multiple target states, laboratory constraints and the momentum of the target wave packet [1,2]. Two different applications for molecular devices will be presented. In the first example control strategies for molecular switches in donorbridge- acceptor systems driven via ultrafast reactions will be discussed [2]. The selected molecules are bistable aromatic compounds, which can be optically switched from one stable isomer to the other, allowing or preventing energy transfer. The second example is the implementation of universal quantum gates and quantum algorithms operating on molecular vibrational qubits [1,3,4].
[1] C. M. Tesch, R. de Vivie-Riedle, Phys. Rev. Lett. 89 (2002) 157901.
[2] D. Geppert, L. Seyfarth, and R. de Vivie-Riedle, App. Phys. B 79 (2004) 987-992.
[3] C. Tesch and R. de Vivie-Riedle, J. Chem. Phys. 121 (2004) 12158-12168.
[4] U. Troppmann and R. de Vivie-Riedle, J. Chem. Phys. 122 (2005) 154105.
