Tunable Electronic Transport in Pd${}_3$O${}_2$Cl${}_2$ Kagome Bilayers: Interplay of Stacking Configuration and Strain

Abstract

Kagome lattice bilayers offer unique opportunities for engineering electronic properties through interlayer stacking and strain. We report a comprehensive first-principles study of Pd${}_3$O${}_2$Cl${}_2$ kagome bilayers, examining four stacking configurations (AA, AA${}^{\prime }$, AB, AB${}^{\prime }$). Our calculations reveal dramatic stacking-dependent band gap modulation from 0.08 to 0.76~eV, with the AB${}^{\prime }$ configuration being the most thermodynamically stable. All stackings exhibit robust mechanical stability with Young's moduli of 54.82-61.97~N/m and ductile behavior suitable for flexible electronics. Carrier effective masses show significant stacking dependence, ranging from 2.39-6.35~$m_0$ for electrons and 0.67-1.55~$m_0$ for holes. Strain engineering of the AB${}^{\prime }$ bilayer demonstrates non-monotonic band gap tuning and asymmetric modulation of carrier masses, with hole effective masses showing stronger strain sensitivity. These results establish Pd${}_3$O${}_2$Cl${}_2$ bilayers as a promising platform for strain-engineered kagome-based quantum devices, where stacking order and mechanical deformation provide complementary control over electronic transport.