Data underlying the research of Z3-vestigial nematic order due to superconducting fluctuations in the doped topological insulators NbxBi2Se3 and CuxBi2Se3

Experimental data taken on a Nb0.25Bi2Se3 single crystal including, magnetoresistance for magnetic fields applied parallel to the Bi2Se3 basal plane for various in-plane directions of the magnetic field, zero-field thermal expansion, specific heat, DC magnetization, zero-field electric resistivity. Magnetostriction at 0.3 K. Description of data: Thermal expansion: Files: alpha90deg.dat, alpha155deg.dat, alpha215deg.dat: thermal expansion measured along 3 different in-plane directions: 90 degrees, 155 degrees, 215 degrees, respectively. First column:T (K), second column DeltaL/L0 Specific heat: File: Cp.dat First column: T (K), second column C/T (mJ/mol/K2) DC magnetization: File: MagZFC.dat and MagFC.dat measured under zero-field cooled (ZFC) and field-cooled (FC) condition. First column: T (K), second column M (emu/cm3/Oe). Zero-field resistivity: File: resistivity.dat, First column: T (K), second column rho (mOhm cm) Magnetoresistance: Various files: MR90deg.dat,.. The in-plane orientation of the magnetic field is indicated in the file name. First column: H (T), second column rho (mOhm cm).