ABSTRACT
This chapter describes an entrant into the emerging devices landscape, the ballistic deflection transistor (BDT), which promises terahertz speeds. It provides an overview of nanoscale devices and their circuit applications. The chapter describes the operation of the BDT, including ballistic transport in two-dimensional electron gas heterostructures. It presents examples of BDT logic gates— an inverter, a two-input NAND, and a two-input general-purpose gate used to construct random logic. The chapter also presents the BDT circuit design methodology, a full adder implementation case study, and a discussion of applications suited for BDTs. It discusses the future work on voltage-mode BDT logic and potential limitations. A major challenge of cascading logic with BDTs is converting the output current of one device into the input voltage of the next device. The BDT provides complementary outputs; thus, a single BDT can act as both an inverter and a buffer.
