Introduction of Sr into Bi2Se3 thin films by molecular beam epitaxy

Abstract

SrxBi2Se3 is a candidate topological superconductor but its superconductivity requires the intercalation of Sr by into the van-der-Waals gaps of Bi2Se3. We report the synthesis of SrxBi2Se3 thin films by molecular beam epitaxy, and we characterize their structural, vibrational and electrical properties. X-ray diffraction and Raman spectroscopy show evidence of substitutional Sr alloying into the structure, while transport measurements allow us to correlate the increasing Sr content with an increased n-type doping, but do not reveal superconductivity down to 1.5K. Our results suggest that Sr predominantly occupies sites within a quintuple layer, simultaneously substituting for Bi and as an interstitial. Our results motivate future density functional studies to further investigate the energetics of Sr substitution into Bi2Se3.

References in corpus (5)

• Odd-parity topological superconductor with nematic order: Application to CuxBi2Se3
• Local Measurements of the Superconducting Pairing Symmetry in CuxBi2Se3
• Solution to the hole-doping problem and tunable quantum Hall effect in Bi${}_2$Se${}_3$ thin films
• Superconductivity by Sr Intercalation in Layered Topological Insulator Bi2Se3
• Possible Lattice and Charge Order in CuxBi2Te2Se