Electronic standing waves on the surface of Bi2Sr2CaCu2O8+δ

✍ Scribed by M. Vershinin; S. Misra; Y. Abe; S. Ono; Y. Ando; A. Yazdani

• Publisher: Elsevier Science
• Year: 2004
• Tongue: English
• Weight: 351 KB
• Volume: 408-410
• Category: Article
• ISSN: 0921-4534
• DOI: 10.1016/j.physc.2004.03.082

✦ Synopsis

Scanning tunneling microscopy (STM) measurements have shown that electronic states at the surface of Bi 2 Sr 2 CaCu 2 O 8þd single crystals form standing wave patterns at temperatures far below the superconducting transition. It has been shown that these patterns are consistent with those expected from the interference of well-defined quasiparticles around the Bi 2 Sr 2 CaCu 2 O 8þd Fermi surface. We have extended STM measurements of these standing wave patterns to higher temperatures and have found that four unit-cell periodicity patterns observed in the superconducting state persist well above T C , in the pseudogap state. In this regime, many different experimental studies of the cuprates have long claimed the absence of well-defined quasi-particles. If the pseudogap regime is indeed devoid of any coherent quasi-particles then our results suggest that other phenomena, such as stripe formation, must play a role in formation of these patterns.