Nanomaterial-based ultra-low-energy device design is one of the prime research areas in nanoscale computation. In ‘more-than-Moore’ technological trends, new device designs with quantum dot nanostructure have become an emerging domain of research. Various quantum dot-based devices, especially quantum dot cellular automata, have been designed both experimentally and by simulation. These quantum devices operate solely on the principle of charge localisation, which accounts for their high speed and ultra-low energy consumption. Quantum dots have an innate ability to confine electrons. As a result, quantum dot formation in a device is highly desirable in order to design quantum devices. Quantum dot implementation with interfacing indium phosphide (InP)–gallium arsenide (GaAs)–indium phosphide nanostructure and quantum dot formation within the redox centres of an allyl molecule are reported in this paper. The formation of the quantum dot is confirmed by the density-of-state studies conducted by the density functional theory calculation on the proposed nanostructures. The possibility of a new device design with two polarised states, namely ‘state x’ and ‘state x −1’, is also explored. Further, outlined in this paper is the design of quantum devices using Python coding, which makes it easier for a programmer to design any kind of complex nanostructure for nanoscale computation.