Reversible optical data storage below the diffraction limit.

Area of Science:

• Quantum information science
• Materials science
• Solid-state physics

Background:

• Color centers in wide-bandgap semiconductors possess metastable charge states.
• These states are optically controllable and exhibit distinct fluorescence and spin properties.
• Previous optical data storage methods were limited by diffraction.

Purpose of the Study:

• To demonstrate selective charge state control of individual color centers within the same diffraction-limited volume.
• To apply this method for high-density, rewritable, multiplexed data storage.
• To explore alternative optical storage concepts for increased capacity and reduced energy consumption.

Main Methods:

• Leveraging local heterogeneity in optical transitions of color centers in diamond (nitrogen vacancies).
• Selective optical excitation for individual point defect control.
• Application to dense color center ensembles for data storage.

Main Results:

• Demonstrated selective charge state control of individual point defects.
• Achieved rewritable, multiplexed data storage in dense color center ensembles.
• Attained an areal storage density of 21 GB/inch² at cryogenic temperatures.

Conclusions:

• Local heterogeneity in optical transitions enables precise control of individual color centers.
• This approach significantly enhances optical data storage density beyond diffraction limits.
• The developed technique offers a promising pathway for next-generation optical storage devices with higher capacity and energy efficiency.