Ballistic two-dimensional lateral heterojunction bipolar transistor

We propose and investigate the intrinsically thinnest transistor concept: a monolayer ballistic heterojunction bipolar based on lateral heterostructure of transition metal dichalcogenides. The device is thinner than Field Effect Transistor because it does not need top or bottom gate, since transport controlled by electrochemical potential base electrode. As typical transistors, collector current undergoes tenfold increase for each 60 mV voltage over several orders magnitude at room temperature, without sophisticated optimization electrostatics. present detailed investigation self-consistent simulations electrostatics quantum both electron holes pnp using MoS$_2$ 10-nm WSe$_2$ emitter collector. Our three-terminal confirm working principle large modulation I$_\text{ON}$/I$_\text{OFF}\sim 10^8$ $\Delta V_{\rm EB}=0.5$ V. Assuming transport, we are able to achieve gain $\beta\sim$ 10$^4$ cutoff frequency up THz range. Exploration rich world nanoscale concepts in 2D materials promising their applications electronics optoelectronics.