Relativistic Fermion on a Ring: Energy Spectrum and Persistent Current

Figure 4

Nature of the energy and current for different values of 𝜅. Here we use (ℏ=𝑐=𝑒=𝑚_𝑒=1) 𝑅=10𝑟_𝑒 and vary the mass. We have taken 𝑚=0.1𝑚_𝑒(𝜅=1), 𝑚=0.05𝑚_𝑒(𝜅=4), and 𝑚=0.01𝑚_𝑒(𝜅=100). 𝑚=0.05𝑚_𝑒 is the critical mass (12) at which energy becomes linear in flux and current attains a constant value 𝐼_sat (13). For 𝜅>4, 𝐼_sat is the lower cutoff of the current.

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