Extended Data Fig. 8: Effect of a biaxial strain on the valence band structure and non-Abelian Berry connection along the direction of quasi-momentum k in the kz = 0 plane of the Brillouin zone.
From: Reconstruction of Bloch wavefunctions of holes in a semiconductor
The strain is chosen as tensile along [001] direction to be consistent with the splitting of the exciton peaks in the absorbance spectrum (Extended Data Fig. 2). a, Valence band structures along \({k}_{x}={k}_{z}=0\) for unstrained (top) and strained (bottom) GaAs. The blue and orange curves represent the heavy-hole and light-hole bands, respectively. b, The magnitude of the diagonal Berry connection matrix element \({{\mathscr{A}}}_{H{H}_{+},H{H}_{+}}\) along the direction of quasi-momentum for unstrained (top) and strained (bottom) GaAs. c, The magnitude of the off-diagonal Berry connection matrix element \({{\mathscr{A}}}_{H{H}_{+},L{H}_{+}}\) along the direction of quasi-momentum for unstrained (top) and strained (bottom) GaAs. For the unstrained case, the Berry connection along the quasi-momentum is identically zero in the plots except for the singularity at \({\boldsymbol{k}}\)=0. The Berry connection is plotted in units of \(a\), which is the lattice constant of GaAs.
