Spin Polarized Current Injection Through HgBr₂ Intercalated Bi2212 Intrinsic Josephson Junctions


To investigate the effect of polarized current on tunneling characteristics of intrinsic Josephson junctions (IJJs), spin-polarized and spin-degenerate current have been injected through the c-axis of HgBr2 intercalated Bi2.1Sr1.5Ca1.4Cu2O 8+δ (Bi2212) single crystals on which 10 x 10 μm 2 mesas have been fabricated. These two spin conditions are achieved by depositing either Au (15 nm)/Co (80 nm)/Au (156 nm) multilayers or single Au film on HgBr2 intercalated Bi2212 with Tc = 74 K followed by photolithography and Ar ion beam etching. The I-V characteristics have been measured with and without a magnetic field parallel to c-axis at 4.2 K. A fine, soft Au wire is used to make a gentle mechanical contact on the top of a particular mesa in the array. Tunneling conductance characteristics were obtained and the magnetic field dependence of sumgap voltage peaks was investigated. These peaks do not change in position with increasing magnetic field for both contact configurations. In addition, the temperature dependence of tunneling characteristics of the IJJs are obtained and existence of pseudogap feature is observed above Tc for HgBr2 intercalated Bi2212.



Second Department

Geosciences and Geological and Petroleum Engineering

Keywords and Phrases

Bismuth compounds; Josephson junction devices; Magnetic fields; Single crystals; Spin polarization; Intrinsic josephson junctions; Pseudogap; Spin polarized current; Electron injection

International Standard Serial Number (ISSN)


Document Type

Article - Journal

Document Version


File Type





© 2007 Institute of Electrical and Electronics Engineers (IEEE), All rights reserved.

Publication Date

01 Jun 2007