Emergence of Interlayer Coherence in Twist-Controlled Graphene Double Layers

Abstract

We report enhanced interlayer tunneling with reduced linewidth at zero interlayer bias in a twist-controlled double monolayer graphene heterostructure in the quantum Hall regime, when the top ($\hat{I}{½}_{\mathrm{T}}$) and bottom ($\hat{I}{½}_{\mathrm{B}}$) layer filling factors are near $\hat{I}{½}_{\mathrm{T}}=\pm 1/2,\pm 3/2$ and $\hat{I}{½}_{\mathrm{B}}=\pm 1/2,\pm 3/2$, and the total filling factor $\hat{I}½=\pm 1$ or $\pm 3$. The zero-bias interlayer conductance peaks are stable against variations of layer filling factor, and signal the emergence of interlayer phase coherence. Our results highlight twist control as a key attribute in revealing interlayer coherence using tunneling.

5 pages, 4 figures, includes supplementary material