English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

We investigated the transport properties of Fe$_{1+y}$Te$_{0.6}$Se$_{0.4}$single crystals with different amounts of excess Fe prepared by O$_2$annealing. The O$_2$ annealing remarkably improves transport properties. Inparticular, a strongly nonlinear Hall resistivity was observed only in thefully-annealed crystal, and the magnetoresistance (MR) is drastically enhancedafter annealing, reaching a value larger than 17% at 16 K and 14 T. The obviouschange of transport properties after the annealing indicates that the bandstructure of Fe$_{1+y}$Te$_{0.6}$Se$_{0.4}$ is affected by the excess Fe. Thenonlinear Hall resistivity and violation of (modified) Kohler's scaling of thelarge MR prove the multiband effects in the Fe$_{1+y}$Te$_{0.6}$Se$_{0.4}$single crystal. The MR for the fully-annealed crystal develops linearly againstmagnetic field from intermediate field (e. g. 2 T at 16 K) to the measurementlimit of 14 T. This phenomenon is interpreted by the existence of Dirac conestate, in which all the Dirac fermions occupy only the lowest Landau level inthe quantum limit.

Multiband Effect and Possible Dirac Fermions in Fe$_{1+y}$Te$_{0.6}$Se$_{0.4}$