Uniaxial pressure derivatives of the critical temperature in Casimir energy-induced superconductivity

Recent advancements suggest that increasing the superconducting critical temperature to room temperature through external pressure may be more effective than alternative methods. External pressure compresses the superconductor, altering its electronic structure, critical temperature, and doping effects. It is widely recognized that, in many cases, external pressure enhances the critical temperature. In superconductors, hydrostatic pressure applied isotropically and uniaxial pressure applied along a specific crystallographic axis exert distinct influences on the critical temperature, with these effects strongly depending on the material's doping level. In this article, based on the theory of Casimir energy-induced superconductivity, we derive explicit equations for calculating the uniaxial pressure derivatives of the critical temperature for underdoped, optimally doped, and overdoped superconductors. The theoretical predictions derived show good agreement with experimental results. This study introduces a novel approach by incorporating variations in doping levels and anisotropic pressure effects within the Casimir energy-induced superconductivity framework, thereby providing a more comprehensive understanding than previous models. According to our analysis, pressure applied along the a or b axes increases the critical temperature $${T}_{c}$$ T c in underdoped and optimally doped cuprate superconductors. In contrast, pressure along the c-axis leads to a decrease. In overdoped cuprate superconductors, pressure along the a or b axes can either increase or decrease $${T}_{c}$$ T c . Conversely, pressure along the c-axis consistently decreases it, similar to the underdoped and optimally doped cases. These findings may also apply to other families of layered superconductors, highlighting the broader relevance of our model. Graphical abstract