Faraday wave

When the vibration frequency exceeds a critical value, the flat hydrostatic surface becomes unstable.

Faraday first described them in an appendix to an article in the Philosophical Transactions of the Royal Society of London in 1831.

The waves can take the form of stripes, close-packed hexagons, or even squares or quasiperiodic patterns.

[4] Faraday waves are used as a liquid-based template for directed assembly of microscale materials including soft matter, rigid bodies, biological entities (e.g., individual cells, cell spheroids and cell-seeded microcarrier beads).

[5] Unlike solid-based template, this liquid-based template can be dynamically changed by tuning vibrational frequency and acceleration and generate diverse sets of symmetrical and periodic patterns.