Superconductors with noncentrosymmetric crystal structures

The area of superconductivity has got more fascinating after the discovery of superconductivity in noncentrosymmetric crystal structures. Experimental evidence for superconductivity in noncentrosymmetric structures provides a platform to understand the interactions and nature of pairing mechanism in superconductors at a microscopic level. The underlying physics in noncentrosymmetric superconductors (NCSs) are not well developed and these studies have paved a path for understanding the possible factors, which significantly affect the superconducting parameters in such systems. In recent years, the unconventional nature of superconductivity in materials lacking inversion symmetry has been studied experimentally and also theoretically. Broken spatial or time reversal symmetries have been discussed in these superconductors. The absence of centre of symmetry leads to asymmetric electronic distribution and antisymmetrically coupled electronic states. Along with superconductivity, some other important physical aspects such as topological band structure, heavy fermionic nature, etc. may be correlated in these studies. A detailed understanding of the unconventional nature of the superconductivity in noncentrosymmetric structures is awaited, we review the current status of the existing information to address the pairing mechanism in these systems. Several noncentrosymmetric superconductors studied in the past and their superconducting properties are discussed to understand the possible pair-mixing scenario in different materials.