Controlled bit flip of period-doubling and discrete time crystalline states in open systems
Phys. Rev. B 112, 024303 – Published 7 July, 2025
DOI: https://doi.org/10.1103/3l49-xdt1
Abstract
In this work, we explore the robustness of a bit-flip operation against thermal and quantum noise for bits represented by the symmetry-broken pairs of the period-doubled states in a classical parametric oscillator and discrete time crystal (DTC) states in an open fully connected spin-cavity system, respectively. The bit-flip operation corresponds to switching between the two period-doubled and DTC states induced by a defect in a periodic drive. The defect is introduced in a controlled manner by linearly ramping the phase of the modulation of the drive. In the absence of stochastic noise, strong dissipation results in a more robust bit-flip operation in which slight changes to the defect parameters do not significantly lower the success rate of bit flips. The operation remains robust even in the presence of stochastic noise when the defect duration is sufficiently large. By considering parameter regimes in which the DTC states in the spin-cavity system do not directly map to the period-doubled states, we reveal that this robustness stems from the system being quenched by the defect towards a new phase that has enough excitation to suppress the effects of the stochastic noise. This allows for precise control of the bit-flip operations by tuning into the preferred intermediate state that the system will enter during a bit-flip operation. We demonstrate this in a modified protocol based on precise quenches of the driving frequency.
