Aharonov-Bohm interferometer in inverted-band <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mi mathvariant="italic">pn</mml:mi></mml:mrow></mml:math> junctions

Inverted-band <a:math xmlns:a="http://www.w3.org/1998/Math/MathML"><a:mrow><a:mi>p</a:mi><a:mi>n</a:mi></a:mrow></a:math> junctions in two-dimensional materials offer a promising platform for electron optics in condensed matter, as they allow to manipulate and guide electron beams without the need for spatial confinement. In this work, we propose the realization of an Aharonov-Bohm (AB) interferometer using such <b:math xmlns:b="http://www.w3.org/1998/Math/MathML"><b:mrow><b:mi>p</b:mi><b:mi>n</b:mi></b:mrow></b:math> junctions. We observe AB oscillations in numerically obtained conductance and analytically identify the conditions for their appearance by analyzing the scattering processes at the <c:math xmlns:c="http://www.w3.org/1998/Math/MathML"><c:mrow><c:mi>p</c:mi><c:mi>n</c:mi></c:mrow></c:math> interface. To support experimental implementation, we also consider junctions with a graded interface, where the potential varies smoothly between the <d:math xmlns:d="http://www.w3.org/1998/Math/MathML"><d:mrow><d:mi>p</d:mi><d:mtext>−</d:mtext></d:mrow></d:math> and <e:math xmlns:e="http://www.w3.org/1998/Math/MathML"><e:mi>n</e:mi></e:math>-doped regions. Our results reveal an abrupt change in the AB-oscillation frequency, which we attribute to a distinct transition in the hybridization across the interface. We verify that our reported AB oscillations are robust to realistic disorder and temperature decoherence channels. Our study paves the way for realizing the Aharonov-Bohm effect in bulk mesoscopic systems without the need for external spatial confinement, offering new possibilities in electron optics.