Toward the laser control of electronic decoherence

Area of Science:

• Quantum Chemistry
• Physical Chemistry
• Molecular Dynamics

Background:

• Controlling electronic decoherence in molecules is a significant challenge.
• Recent theories suggest manipulating initial electronic superposition states can control decoherence rates.
• This control is observed in systems with relaxation and pure-dephasing channels for initially separable electron-nuclear states.

Purpose of the Study:

• To investigate the creation of initial superposition states and quantum control of electronic decoherence using laser pulses.
• To determine if one-photon laser control of decoherence is applicable to stationary molecular states.
• To develop a scheme for recovering laser control of electronic decoherence from stationary states.

Main Methods:

• Weak-field one-photon photoexcitation with few-cycle laser pulses of definite carrier envelope phase (CEP).
• Analysis of decoherence control for initially separable and non-separable (stationary) electron-nuclear states.
• Development and application of a two-pulse control scheme involving vibronic superposition states.

Main Results:

• One-photon laser control of electronic decoherence is achievable for initially separable electron-nuclear states.
• This one-photon control disappears for stationary molecular states, even when they closely approximate separable states.
• A two-pulse scheme successfully recovers laser control of electronic decoherence from stationary states by inducing interference.

Conclusions:

• Laser control of electronic decoherence is feasible via manipulation of initial superposition states with specific laser pulses.
• The use of widely adopted initially factorizable system-bath states can introduce artifacts in open quantum systems research.
• A two-pulse strategy offers a viable method for controlling electronic decoherence in stationary molecular states.