Toward the realization of chiral qubit: quantum computing with chirality

The quantum chiral anomaly enables a non-dissipative current in the presence of chirality imbalance. We proposed to utilize the chiral anomaly for the designs of qubits potentially capable of operating at THz frequency and at room temperature. The proposed chiral qubit is a microscopic-scale ring made of a Weyl semimetal, with the and states corresponding to the symmetric and antisymmetric superpositions of chiral currents circulating along the ring clockwise and counter-clockwise. In this talk, we report our investigations into several topological control principles driven by quantum coherence and understanding the time dependence of topological phase transition. These investigations included an experimental demonstration of a unique phonon-assisted topological switching in a Dirac semimetal, and giant dissipationless topological photocurrent that carries the imprints of chirality of Weyl fermions under zero magnetic field. The experimental results are compared with the dynamic phonon driving Weyl phases given theoretically by employing first-principles and effective Hamiltonian methods.