Mott insulating state of IrO6 honeycomb monolayer structured in ilmenite-type oxide superlattice

Quantum magnetism based on the Kitaev honeycomb model has been intensively studied both by theoretical material design and experimental materialization. In contrast to the considerable progress of theoretical modeling and experiments on bulk crystals, it is still difficult to find a candidate material applicable to thin films and devices toward future quantum computation. Here we clearly demonstrate a Mott insulating state of <a:math xmlns:a="http://www.w3.org/1998/Math/MathML"><a:mrow><a:mi>Ir</a:mi><a:msub><a:mi mathvariant="normal">O</a:mi><a:mn>6</a:mn></a:msub></a:mrow></a:math> honeycomb monolayer structured in ilmenite-type <c:math xmlns:c="http://www.w3.org/1998/Math/MathML"><c:mrow><c:mrow><c:mi>Mg</c:mi><c:mtext>−</c:mtext><c:mi>Ir</c:mi><c:mtext>−</c:mtext><c:mi mathvariant="normal">O</c:mi></c:mrow><c:mo>/</c:mo><c:mi>MgTi</c:mi><c:msub><c:mi mathvariant="normal">O</c:mi><c:mn>3</c:mn></c:msub></c:mrow></c:math> superlattices, which is a good candidate of the Kitaev honeycomb magnet applicable to devices. Electronic states detected by photoelectron spectroscopy agree well with those in theoretical band calculations. The stabilized superlattice with the Mott gap state is a promising platform to examine the device physics of the Majorana fermions and the <f:math xmlns:f="http://www.w3.org/1998/Math/MathML"><f:msub><f:mi>Z</f:mi><f:mn>2</f:mn></f:msub></f:math> fluxes in the Kitaev honeycomb model, suggesting the thin-film techniques are quite beneficial for triggering the exploration of quantum computation in designable and evolvable heterostructures.