- Tytuł:
- Scanning Tunneling Spectroscopy Sensitive to Layer Structure of BSCCO
- Autorzy:
-
Aleszkiewicz, M.
Aleszkiewicz, P.
Raułuszkiewicz, J. - Powiązania:
- https://bibliotekanauki.pl/articles/1963289.pdf
- Data publikacji:
- 1997-03
- Wydawca:
- Polska Akademia Nauk. Instytut Fizyki PAN
- Tematy:
-
61.16.Ch
68.65.+g
74.72.Hs - Opis:
- Scanning tunneling microscopy images and scanning tunneling spectroscopy characteristics were measured at 4.2 K in liquid helium bath on the cleaved in air a-b surface of Bi$\text{}_{2}$Sr$\text{}_{2}$CaCu$\text{}_{2}$O$\text{}_{8}$ (BSCCO-2212). Electronic densities of states and superconductivity parameters Δ and Γ evaluated from dI/dV characteristics depend on tip-sample distance s: with shortening of the distance s superconducting gap structure becomes more distinct, i.e. Δ increases and Γ decreases. We explain this phenomenon as a non-vacuum tunneling, where for longer s tunneling electrons reach only the surface contamination layer on non-metallic BiO top-surface layer, whereas for shorter s tunneling electrons penetrate also deeper lying CuO layers reflecting their superconducting properties. The dependence of Δ on s is evaluated. This result allows to understand better the non-vacuum scanning tunneling microscopy imaging: by adjusting properly the tip-sample distance one can select suitable local density of states contributing dominantly to the scanning tunneling microscopy images taken on BSCCO.
- Źródło:
-
Acta Physica Polonica A; 1997, 91, 3; 597-604
0587-4246
1898-794X - Pojawia się w:
- Acta Physica Polonica A
- Dostawca treści:
- Biblioteka Nauki