Reconfigurable bipolar transistors enabled by breathing-Kagome Nb ₃ Cl ₈

The breathing Kagome semiconductor Nb₃Cl₈ offers unique electronic properties, which has emerged as a prominent area of research in condensed matter physics. However, the realization of functional devices based on breathing kagome materials remains a challenge. Here, we fabricate dual-gate Nb₃Cl₈ field-effect transistors (FETs) using h-BN or SiO₂ as the gate dielectric. While SiO₂-gated devices exhibit significant hysteresis, h-BN gating suppresses this effect and reveals distinct bipolar conduction with an on/off ratio exceeding 10³. Temperature-dependent measurements quantify the carrier injection barriers. Basing on the bipolarity of the Nb₃Cl₈ semiconductor, we fabricated a programmable transistor with two aligned gates, which can be switched between PN, NP, PP and NN configurations <i>via</i> controlling the two semi-gates. Furthermore, convolutional image processing using diverse crossbar kernels is demonstrated based on the programmable bipolar transistor, showcasing its potential for neuromorphic computing and adaptive electronics.