Emergent strong zero mode through local Floquet engineering

Decoherence is the main obstacle for quantum information processing and fault-tolerant quantum computation. That's why it is extremely important to explore ways to suppress the decoherence of a quantum system. The constituents of a generic interacting many-body system usually decohere under their own dynamics but some sophisticated (integrable) interaction can lead to long-lived emergent quasiparticles, for example, edge Majorana zeromode of a Kitaev chain. The notion of strong zeromode (SZM) was extended to systems with genuine (yet integrable) interaction but their existence in non-integrable systems has always been an open question. In this talk, I will discuss how local Floquet engineering can be used to help emerge a SZM in a non-integrable system. Individual spins of a non-integrable system (spin-1/2 staggered Heisenberg model with a global field) can not be dynamically frozen even by the most optimal choice of drive parameters. Interestingly, a special sequence of optimally driven sites can stabilize a SZM, enhancing the decoherence time of the edge spin exponentially in system size.

Refs : 

1) P. Fendley, Strong zero modes and eigenstate phase transitions in the XYZ/interacting Majorana chain, J. Phys. A: Math. Theor. 49, 30LT01 (2016).

2) B. Mukherjee et al, Emergent strong zero mode through local Floquet engineering, Arxiv: 2306.01835.