THE STUDY OF UPPER CRITICAL MAGNETIC FIELD, COHERENCE LENGTH AND PENETERATION DEPTH OF SUPER CONDUCTING OSMIUM DIBORIDE (OsB2)

Abstract Osmium Diboride (OsB2) superconductor is type II superconductor which ha slower critical magnetic field (Hc1) and upper critical magnetic field (Hc2). The upper critical field is the magnetic flux density that completely suppresses superconductivity in a type-II superconductor at 0 K (absolute zero). In this work, the upper critical magnetic field (Hc2), the Ginzburg-Landau coherence length (ξGL) and penetration depth (λGL) of Osmium Diboride (OsB2) superconductor have been theoretically investigated by employing the Ginzburg-Landau(GL) phenomenological Equation. Mathematical expression for upper critical magnetic field (Hc2), Ginzburg-Landau coherence length (ξGL) and penetration depth (λGL) of Osmium Diboride (OsB2) superconductor have been obtained using this phenomenological equation. Considering experimental values and use it in the obtained expression, the phase diagram of upper critical magnetic field as a function of temperature, Ginzburg-Landau coherence length (ξGL) as a function of temperature and penetration depth (λGL) as function of temperature have been plotted. The graph of upper critical magnetic field (Hc2) as a function of temperatures shows that, the upper critical magnetic field decreases as temperature increases and reaches to zero at the critical temperature of superconducting OsB2. The graph GL coherence length versus temperature (T) shows that the GLcoherence length increases with temperature and diverge as T→Tc ξGL(o) has the same value with the BCS coherence length (ξGL(o)=ξo). GL penetration depth versus temperature (T) diagram reveals that the penetration depth increases asymptotically as the temperature approaches Tc. These theoretical finding of (ξGL), (λGL) andH2 are well agree with experimental observations upper critical magnetic field (Hc2 of super conducting OsB2 is inversely proportional to the GL coherence length Our findings are in agreement with experimental observations.