Sandeep Khare - Academia.edu (original) (raw)

Papers by Sandeep Khare

Science, 1991

The appearance of superconductivity at relatively high temperatures in alkali metaldoped C,, full... more The appearance of superconductivity at relatively high temperatures in alkali metaldoped C,, fullerene provides the challenge to both understand the nature and origin of the superconductivity and to determine the upper limit of the superconducting transition temperature (T,). Towards the latter goal, it is shown that doping with potassium-thallium and rubidium-thallium alloys in the 400 to 430°C temperature range increases the Tc of Cao/C,, mixtures to 25.6 K and above 45 K, respectively. Similar increases in Tc were also observed upon analogous doping of pure C,,. Partial substitution of potassium with thallium in interstitial sites between C,, molecules is suggested by larger observed unit cell parameters than for the K,C,, and &C,, phases. Contrary to previous results for C,, doped with different alkali metals, such expansion does not alone account for the changes in critical temperature.

Science, 1991

The appearance of superconductivity at relatively high temperatures in alkali metaldoped C,, full... more The appearance of superconductivity at relatively high temperatures in alkali metaldoped C,, fullerene provides the challenge to both understand the nature and origin of the superconductivity and to determine the upper limit of the superconducting transition temperature (T,). Towards the latter goal, it is shown that doping with potassium-thallium and rubidium-thallium alloys in the 400 to 430°C temperature range increases the Tc of Cao/C,, mixtures to 25.6 K and above 45 K, respectively. Similar increases in Tc were also observed upon analogous doping of pure C,,. Partial substitution of potassium with thallium in interstitial sites between C,, molecules is suggested by larger observed unit cell parameters than for the K,C,, and &C,, phases. Contrary to previous results for C,, doped with different alkali metals, such expansion does not alone account for the changes in critical temperature.