Fundamental limits in computing

The overarching goal of our research program is to understand how to design and fabricate scaled, compatible electronic devices and systems that can operate close to the fundamental physical limits of computing and even overcome those. Having driven the information revolution over the last couple of decades, CMOS scaling has come to end. Yet, there is an enormous room for improvement in the today’s computing substrates. This is because there is a significant gap between the performance of the state-of-the-art and the fundamental limits of computing. The theoretical energy minimum for an irreversible logic or memory operation is of the order of kT; today’s transistor technology dissipates six to seven orders of magnitude larger energy at the functional unit level. Such physical limits originate due to considerations related to thermodynamics, statistical mechanics, quantum mechanics and electromagnetism.   Examples of these limits include the Boltzmann limit, the Landauer limit, the von Neumann limit and so on. Building upon the foundation laid by the likes of von Neumann, Landauer, Bennett and Feynman, we bring in the new physics and interesting phenomena in emerging and quantum materials such as ferroelectrics, antiferroelectrics, and strongly correlated systems to realize novel-yet-practical-and-compatible nanoelectronic devices that achieve the computational performance at par with the fundamental physical limits. The effects of such nanoelectronic computing devices ripple through the entire hierarchy of computing–we collaborate with circuit designers, computer architects, and algorithm experts to assess the impact of our physics-materials-device level work at the full system level.


Tasneem et al. DRC (2018). Khan et al. Nature Mater. 14, 182 (2015); Khan et al. IEDM (2011); Khan et al. Appl. Phys. Lett. 99, 113501 (2011).

Foundational work:

Landauer. IBM J. Res. Dev. 5.3, 183 (1961); Likharev, Int’l J. Theoretical Phys. 21, 311 (1982); Bennette, Int’l J. Theoretical Phys. 21, 905 (1982).