Nbse2 Lattice Constant

Superconductivity Anisotropy in NbSe2: Lattice Parameters and Magnetic Field Effects

Introduction

Superconductivity is a phenomenon where materials exhibit zero electrical resistance and expel magnetic fields below a certain temperature. In the case of 2H-NbSe2, a layered transition metal dichalcogenide, superconductivity has been observed with a critical temperature of around 7 Kelvin.

Lattice Parameters and Structural Details

The lattice parameters of 2H-NbSe2 were determined to be a = 3.4453 Å and c = 12.5482 Å, as determined from X-ray diffraction measurements. These values represent the lengths of the a and c axes of the primitive cell. It's important to note that calculated cell volumes tend to be overestimated for materials like 2H-NbSe2.

Anisotropy in the Upper Critical Field

Studies on 2H-NbSe2 have shown a significant anisotropy in its upper critical field, which is the maximum magnetic field that can suppress superconductivity. The anisotropy is attributed to the layered structure of the material, with the upper critical field being three times larger perpendicular to the layers than parallel to them.

Implications for Superconductivity

The observed anisotropy in the upper critical field suggests that the superconducting properties of 2H-NbSe2 are strongly influenced by its layered structure. This anisotropy could have implications for the design and performance of superconducting devices based on NbSe2.

Conclusion

The lattice parameters and magnetic field anisotropy in 2H-NbSe2 are important factors in understanding its superconducting behavior. The large anisotropy in the upper critical field stems from the layered structure of the material and could influence the application of NbSe2 in superconducting technologies.