Solid-state quantum computers based on quantum dots and dopants in semiconductors such as silicon offer the promise of scalability and long coherence times. However, the design and implementation of robust semiconductor qubits are challenging due to the complexity of the solid-state environment. Details of band degeneracies, atomic scale disorder, electrostatic potential, device geometry, electron-phonon interactions, many-particle effects, and spin-spin interactions, and time-dependence need to be captured in theoretical models to understand measurements of state-of-the-art experiments and to provide device design guidance. The conventional electrostatic modeling tools (TCAD) that are used for transistor modeling are not sufficient in this regime of electronics. Our group has developed a software tool called NEMO (Nano-Electronic MOdeling) that aims to serve as a device design tool in this new regime of electronics. NEMO represents the single and multi-particle Schrodinger equation on an atomic orbital basis taking into account all the above-mentioned interactions.

Relevant Publications:

Y. Hsueh, H. Buch, Y. Tan, Y. Wang, L. Hollenberg, G. Klimeck, M. Simmons, R. Rahman,, "Spin-lattice relaxation times of single donors and donor clusters in silicon", Phys. Rev. Lett. 113, 246406 (2014)

B Weber, Y-H. Tan, S. Mahapatra, T. Watson, H. Ryu, R. Rahman, L. Hollenberg, G. Klimeck, M. Simmons, "Spin blockade and exchange in Coulomb-confined silicon double quantum dots", Nat. Nanotechnol. 9, 430–435 (2014)

J. Salfi, J. Mol, R. Rahman, G. Klimeck, M. Simmons, L. Hollenberg, S. Rogge, "Spatially resolving valley quantum interference of a donor in silicon", Nat. Mater. 13, 605–610 (2014)