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Mott gap collapse in lightly hole-doped Sr_2-xK_xIrO₄.

ABSTRACT: The evolution of Sr₂IrO₄ upon carrier doping has been a subject of intense interest, due to its similarities to the parent cuprates, yet the intrinsic behaviour of Sr₂IrO₄ upon hole doping remains enigmatic. Here, we synthesize and investigate hole-doped Sr_2-xK_xIrO₄ utilizing a combination of reactive oxide molecular-beam epitaxy, substitutional diffusion and in-situ angle-resolved photoemission spectroscopy. Upon hole doping, we observe the formation of a coherent, two-band Fermi surface, consisting of both hole pockets centred at (?, 0) and electron pockets centred at (?/2, ?/2). In particular, the strong similarities between the Fermi surface topology and quasiparticle band structure of hole- and electron-doped Sr₂IrO₄ are striking given the different internal structure of doped electrons versus holes.

SUBMITTER: Nelson JN

PROVIDER: S-EPMC7244596 | biostudies-literature | 2020 May

REPOSITORIES: biostudies-literature

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Mott gap collapse in lightly hole-doped Sr2-xKxIrO4.

Nelson J N JN Parzyck C T CT Faeth B D BD Kawasaki J K JK Schlom D G DG Shen K M KM

Nature communications 20200522 1

The evolution of Sr2IrO4 upon carrier doping has been a subject of intense interest, due to its similarities to the parent cuprates, yet the intrinsic behaviour of Sr2IrO4 upon hole doping remains enigmatic. Here, we synthesize and investigate hole-doped Sr2-xKxIrO4 utilizing a combination of reactive oxide molecular-beam epitaxy, substitutional diffusion and in-situ angle-resolved photoemission spectroscopy. Upon hole ...[more]

PMID: 32444617

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