A collaboration between researchers at the University of Western Australia and the University of California Merced has provided a new way to measure tiny forces and use them to control objects.
The research, published yesterday in Nature Physics ( “Casimir spring and dilution in macroscopic cavity optomechanics”), it was a good team effort. The professor Michael Tobar, of the UWA School of Physics, Mathematics and Computing and dr. Jacob Pat at the University of Merced have joined efforts to control the Casimir effect.
Professor Tobar said that the result allowed a new way to manipulate and control macroscopic objects without contact, allowing for greater sensitivity without adding leaks.
What is the Casimir effect
Once believed to be of exclusively academic interest, this little force known as the Casimir effect is now attracting interest in fields such as metrology (the science of measurement) and sensing.
“If we can measure and manipulate the Casimir force on objects, we will have the ability to improve its sensitivity by reducing mechanical losses. This will have a good impact on the energy, science and technology,” said Professor Tobar.
To understand what it is about, a premise must be made: in "nothingness" there is no nothingness. In reality, there is no such thing as a perfect vacuum. Even in empty space at zero temperature, virtual particles such as photons exert an influence and fluctuate.
“These fluctuations interact with objects placed in a vacuum and actually increase in magnitude as the temperature increases, causing a measurable force from “nothingness.” This photo is known as the Casimir effect.
“Now we have shown that it is also possible to use force to do interesting things,” says the researcher. “But to do that, we need to develop precision technology that allows us to control and manipulate objects with this force.”
Professor Tobar said the researchers were able to measure the Casimir effect and manipulate objects through a precision microwave photonic cavity.
A device known as a reentrant cavity, at room temperature, “moved” a thin metal membrane at a distance as large as a speck of dust.
“We took advantage of the Casimir effect between objects. This allowed us orders of magnitude improvement in force sensitivity and the ability to control the mechanical state of the membrane.”