Fig. 1: Creating a Chern junction in MnBi2Te4.
From: Topological current divider in a Chern insulator junction
a–c Concept of the junction. a A thinner MBT flake (Domain I) hosts a chiral edge state with Chern number C = 1 while a thicker flake (Domain II) hosts two chiral edge conduction channels with C = 2. b A Chern junction is formed at a step in thickness in a single flake. c–d Show two possible scenarios for the chiral edge states at the junction. e–g Characterization of Device 1, which contains a 4-layer (Domain I) to 6-layer (Domain II) junction. All data are taken at T = 50 mK. e Hall resistance Ryx as a function of back gate voltage Vbg and magnetic field µ0H for Domain I. The blue dashed line is the contour Ryx = 0.98 h/e2 and surrounds the parameter region where CI = 1. f Similar measurements for Domain II. The black line is at Ryx = 0.98 h/e2 and indicates the parameter region where CII = 1 is located, while the green dashed line is at Ryx = 0.49 h/e2 and indicates where CII = 2 is located. g Overlaid contours from (e,f). The parameter region where the Chern junction exists (CI = 1, CII = 2) is shaded orange, and the region where no junction is expected (CI = 1, CII = 1) is shaded blue.
