biostudies-literatureKwan YHSwiss National Science Foundation52https://www.ebi.ac.uk/biostudies/studies/S-EPMC12893902biostudies-literatureUnknown9(1)The experimental discovery of fractional Chern insulators (FCIs) in moiré materials raises the question of whether their time-reversal invariant analogs, fractional topological insulators (FTIs), can also be realized in these platforms. We address this via exact diagonalization calculations in both a Landau level (LL) model and continuum model for twisted MoTe₂, and extract principles for engineering FTIs in realistic conditions. For the spinful LL model at filling ν=13+13 , we show that a suppression of the short-range component of the interaction is important to stabilize the FTI. For twisted MoTe₂ at ν=-43 , we find that a short-range attraction <i>g</i> on top of the screened Coulomb interaction is needed to realize an FTI. We discuss how this threshold value of <Communications physicsRegarding the existence of abelian fractional topological insulators in twisted MoTe&lt;sub&gt;2&lt;/sub&gt; and related systems.PMC12893902213805Dagnino AKJiang YRegnault NBernevig BANeupert TWagner GKwan YHYu JXu XfalseRegarding the existence of abelian fractional topological insulators in twisted MoTe&lt;sub&gt;2&lt;/sub&gt; and related systems.The experimental discovery of fractional Chern insulators (FCIs) in moiré materials raises the question of whether their time-reversal invariant analogs, fractional topological insulators (FTIs), can also be realized in these platforms. We address this via exact diagonalization calculations in both a Landau level (LL) model and continuum model for twisted MoTe₂, and extract principles for engineering FTIs in realistic conditions. For the spinful LL model at filling ν=13+13 , we show that a suppression of the short-range component of the interaction is important to stabilize the FTI. For twisted MoTe₂ at ν=-43 , we find that a short-range attraction <i>g</i> on top of the screened Coulomb interaction is needed to realize an FTI. We discuss how this threshold value of <2026-01-01T00:00:00Z20262026-07-15T22:01:42.186Z2026-07-09T13:09:14.01ZS-EPMC128939024169564210.1038/s42005-025-02483-6