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تسجيل مستخدم جديد$0$-$pi$ transitions in a Josephson junction of irradiated Weyl semimetal
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We propose a setup for the experimental realization of unexpected and anisotropic $0$-$pi$ transitions of the Josephson current, in a junction whose link is made of irradiated Weyl semi-metal (WSM), due to the presence of chiral nodes. We show using a Greens function technique that the Josephson current through a time-reversal symmetric WSM has anisotropic periodic oscillations as a function of $k_0L$, where $k_0$ is the (relevant) separation of the chiral nodes and $L$ is the length of the sample. This is unexpected, for time-reversal symmetric systems, although it has been shown earlier for time-reversal symmetry breaking WSMs. We then show that the effective value of $k_0$ can be tuned with precision by irradiating the sample with photons resulting in $0$-$pi$ transitions of the critical current. Finally, we discuss the robustness of our setup.
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