Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Maximum lateral acoustic force FAx of 10-W π and 2π radially-varying phase beams versus the ratio of the sphere diameter to beam width η. FAx diminishes for small or large η. The π-radial beam rings have the same acoustic intensity, and both can trap spheres as FAx reaches a maximum close to η = 1 and 2. The 2π-radial follows a smoother shape where maximum FAx is centered at η ≈ 1, since the inner ring has higher intensity and is the effective trapping ring.
