Abstract

We decompose the superfluid weight Ds of magic-angle twisted bilayer graphene (MATBG) into conventional (band-velocity) and geometric (interband-coherence) contributions using a band-basis current operator splitting applied to the Bistritzer-MacDonald continuum model. In the flat-band subspace, quantum geometry accounts for 22–26% of Ds at charge neutrality depending on pairing symmetry, with cross terms vanishing to machine precision. Including remote bands raises the geometric fraction to about 55–58%, while Dconv_s converges to within 2%. The geometric fraction peaks near the nu = ±2 fillings where superconductivity is strongest, and is insensitive to gap magnitude in the experimentally relevant range.

Abstract

We decompose the superfluid weight Ds of magic-angle twisted bilayer graphene (MATBG) into conventional (band-velocity) and geometric (interband-coherence) contributions using a band-basis current operator splitting applied to the Bistritzer-MacDonald continuum model. In the flat-band subspace, quantum geometry accounts for 22–26% of Ds at charge neutrality depending on pairing symmetry, with cross terms vanishing to machine precision. Including remote bands raises the geometric fraction to about 55–58%, while Dconv_s converges to within 2%. The geometric fraction peaks near the nu = ±2 fillings where superconductivity is strongest, and is insensitive to gap magnitude in the experimentally relevant range.

Abstract

We decompose the superfluid weight Ds of magic-angle twisted bilayer graphene (MATBG) into conventional (band-velocity) and geometric (interband-coherence) contributions using a band-basis current operator splitting applied to the Bistritzer-MacDonald continuum model. In the flat-band subspace, quantum geometry accounts for 22–26% of Ds at charge neutrality depending on pairing symmetry, with cross terms vanishing to machine precision. Including remote bands raises the geometric fraction to about 55–58%, while Dconv_s converges to within 2%. The geometric fraction peaks near the nu = ±2 fillings where superconductivity is strongest, and is insensitive to gap magnitude in the experimentally relevant range.

Abstract

We decompose the superfluid weight Ds of magic-angle twisted bilayer graphene (MATBG) into conventional (band-velocity) and geometric (interband-coherence) contributions using a band-basis current operator splitting applied to the Bistritzer-MacDonald continuum model. In the flat-band subspace, quantum geometry accounts for 22–26% of Ds at charge neutrality depending on pairing symmetry, with cross terms vanishing to machine precision. Including remote bands raises the geometric fraction to about 55–58%, while Dconv_s converges to within 2%. The geometric fraction peaks near the nu = ±2 fillings where superconductivity is strongest, and is insensitive to gap magnitude in the experimentally relevant range.