Exploring quantum chaos within a single 123-Sb donor in silicon*

The 123-Sb atom is a group-V element with a nuclear spin quantum number of 7/2, resulting in an 8-dimensional Hilbert space. This atom can be implanted in a silicon Metal-Oxide-Semiconductor structure, and its quantum state can be controlled using the same infrastructure that has been proven to yield high-fidelity control [1] and single-shot readout [2] on the 31-P donor. The key difference in 123-Sb is that the nucleus possesses a quadrupole moment, which can introduce a quadratic term in the spin Hamiltonian when the atom is placed in a strained silicon crystal. By further adding a strong periodic drive, this results in a single-atom quantum system that accurately maps a classically chaotic one: the driven nonlinear top [3]. Therefore, we can engineer a highly controllable, individual quantum system that enables an experimental study of the emergence of chaos and the quantum-to-classical crossover [3]. In this presentation, we will provide a detailed theoretical description of the system, as well as initial results on the spectrum and coherence times of a 123-Sb donor.

[1] J.P. Dehollain et al., New J. Phys. 18, 103018 (2016)
[2] J.J. Pla et al., Nature 496, 334 (2013)
[3] V. Mourik et al., arXiv:1703.04852 (2017)