New Experiment on Casimir Force Yields Surprise

This recent study, published online on Sept. 27 in the Nature Communications, breaks new ground in the standard measurements of the Casimir effect known to scientists. The experiment used nanostructured (micro-ridged) metallic plates to suppress the force to a much lower rate than ever recorded previously, said Ricardo Decca, Ph.D., professor of physics at IUPUI.

"These results build upon our expertise in the measurement of the Casimir effect. At IUPUI, we have the most precise determinations of this interaction," said Decca, one of nine co-authors in the discovery. He also is the director of the graduate program in the Department of Physics at IUPUI and co-director of the Nanoscale Imaging Center.

"Based on previous knowledge, the attraction discovered here should not have decreased as much as it did. There was still an attraction measured but not near the levels typically found," Decca said.

[...]

The reduced attraction was measured using a metal-coated sphere attached to an oscillator mounted above two electrodes. A metallic, nanostructured grating was attached to an optical fiber, and the interaction occurred as the sphere and grating were moved closer to one another.

The experiment revealed the Casimir pressure was reduced at more than twice the expected levels when the sphere and the grating surface were separated from one another by up to 500 nanometers.

Although excited for the results thus far, the research team noted in the publication that much more analysis and study is needed to determine to true breadth of their impact. The results, however, open up new possibilities in the study of an often-debated phenomenon and could lead to more scientific activity in this field.