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arXiv · 2504.04900

Controlled bit-flip of period-doubling and discrete time crystalline states in open systems

Roy D. Jara Jr.·Phatthamon Kongkhambut·Hans Keßler·Andreas Hemmerich·Jayson G. Cosme
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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 (PD) states in a classical parametric oscillator and discrete time crystal (DTC) states in a fully-connected open spin-cavity system, respectively. The bit-flip operation corresponds to switching between the two PD and DTC states induced by a defect in a periodic drive, 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. The fluctuations also enhance the success rate of the bit-flip below the critical defect duration needed to induce a switch. By considering parameter regimes in which the DTC states in the spin-cavity system do not directly map to the PD states, we reveal that this robustness is due to 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.

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Roy D. Jara Jr., Phatthamon Kongkhambut, Hans Keßler, Andreas Hemmerich, Jayson G. Cosme. 2025-07-08. Controlled bit-flip of period-doubling and discrete time crystalline states in open systems. https://doi.org/10.1103/3l49-xdt1

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