Restoring the Coherence of Quantum Emitters through Optically Driven Motional Narrowing Forces

Area of Science:

• Quantum physics
• Quantum optics
• Condensed matter physics

Background:

• Quantum states are susceptible to decoherence from environmental interactions.
• Spectral diffusion in quantum emitters complicates coherence maintenance.
• Controlling environmental fluctuations is key to preserving quantum coherence.

Purpose of the Study:

• To demonstrate motional narrowing in a quantum system.
• To investigate the impact of motional narrowing on quantum emitter properties.
• To explore methods for enhancing quantum coherence in noisy environments.

Main Methods:

• Utilizing optically induced motional forces to control environmental electrical fields.
• Employing a single quantum emitter (Te2 molecule in ZnSe) to study spectral diffusion.
• Analyzing changes in energy, line shape, and line width under motional narrowing conditions.

Main Results:

• Motional narrowing was successfully achieved across various experimental regimes.
• The phenomenon proved effective irrespective of initial disorder or charge reservoir states.
• Accelerating spectral diffusion into the THz range facilitated approaching the optimal coherence limit.

Conclusions:

• Motional narrowing is a viable strategy for preserving quantum coherence in the presence of environmental noise.
• The technique is broadly applicable to quantum systems with controllable environmental fluctuations.
• Motional narrowing reduces the dependency on highly purified materials and sophisticated device fabrication.