Coherent correlation imaging for resolving fluctuating states of matter

Area of Science:

• Condensed Matter Physics
• Materials Science
• Nanotechnology

Background:

• Stochastic transitions and fluctuations are common in nanometre-scale systems, particularly with disorder.
• Observing these phenomena is challenging due to a trade-off between spatial and temporal resolution.

Purpose of the Study:

• To develop a novel imaging technique, coherent correlation imaging (CCI), to overcome spatial-temporal resolution limitations.
• To study previously unobservable magnetic fluctuations in disordered nanoscale systems.

Main Methods:

• Developed CCI by classifying camera frames in Fourier space and averaging same-state frames.
• Achieved high temporal resolution using a correlation-based similarity metric and hierarchical clustering to minimize misclassification.
• Applied CCI to analyze magnetic fluctuations in a degenerate magnetic stripe domain state.

Main Results:

• Uncovered an intricate network of over 30 discrete states and transitions in the magnetic system.
• Reconstructed the pinning energy landscape using spatiotemporal data.
• Provided a microscopic explanation for the observed dynamics.

Conclusions:

• CCI overcomes fundamental resolution limits, enabling direct observation of nanoscale dynamics.
• The technique is applicable to emerging high-coherence X-ray sources.
• Opens new avenues for studying phase transitions, pinning effects, topology, and superconductivity.