Abstract
Critical fluctuations of some order parameters describing a fluid generate long-range forces between boundaries. Here, we discuss fluctuation-induced forces associated with a disordered Landau-Ginzburg model defined in a -dimensional slab geometry . In the model the strength of the disordered field is defined by a nonthermal control parameter. We study a nearly critical scenario, using the distributional zeta-function method, where the quenched free energy is written as a series of moments of the partition function. In the Gaussian approximation, we show that for each moment of the partition function, and for some specific strength of the disorder, the nonthermal fluctuations, associated with an order parameterlike quantity, become long ranged. We demonstrate that the sign of the fluctuation-induced force between boundaries depends in a nontrivial way on the strength of the aforementioned nonthermal control parameter.
- Received 20 January 2022
- Accepted 25 April 2022
DOI:https://doi.org/10.1103/PhysRevD.105.105014
© 2022 American Physical Society