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تسجيل مستخدم جديدSurface superconducting states in a polycrystalline MgB$_{2}$ sample
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We report results of dc magnetic and ac linear low-frequency study of a polycrystalline MgB$_2$ sample. AC susceptibility measurements at low frequencies, performed under dc fields parallel to the sample surface, provide a clear evidence for surface superconducting states in MgB$_2$.
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