– Magneto-optical imaging reveal that below 10 K the penetration of magnetic flux in MgB2 films is dominated by dendritic structures abruptly formed in response to an applied field. The dendrites show a temperature-dependent morphology ranging from quasi-1D at 4 K to large tree-like structures near 10 K. This behaviour is responsible for the anomalous noise found in magnetization curves, and st...

Using Korringa-Kohn-Rostoker coherent-potential approximation in the atomicsphere approximation (KKR-ASA CPA) method for taking into account the effects of disorder, Gaspari-Gyorffy formalism for calculating the electron-phonon coupling constant λ, and Allen-Dynes equation for calculating Tc, we have studied the variation of Tc in Mg1−xTaxB2 alloys as a function of Ta concentration. Our results...

Magnezyum diborür, roket yakıtlarında başlatıcı ve hızlandırıcı olarak kullanılmaktadır. Bu nedenle, yüksek verimlilikte veya saflıkta sentezlenmesi savunma sanayinde önemli bir yer tutmaktadır. çalışmada, diborür sentezi, elementel magnezyum (Mg) Bor (B) kullanılarak mekanokimyasal yöntem ile argon gazı atmosferinde gerçekleştirildi. Öğütme süresi, bilya/toz kütlesel oranı, reaksiyon girdileri...

We provide here experimental data on the phonon density-of-states of MgB2 obtained by the inelastic neutron scattering technique. The measurements were performed for the natural boron-based magnesium diboride with use of a time-of-flight neutron spectrometer. Several phonon bands were observed in the phonon spectrum at energies of about 33, 55, 82 and 99 meV. We show that the cutoff energy of t...

We report observation of Leggett's collective mode in a multiband MgB2 superconductor with Tc=39 K arising from the fluctuations in the relative phase between two superconducting condensates. The novel mode is observed by Raman spectroscopy at 9.4 meV in the fully symmetric scattering channel. The observed mode frequency is consistent with theoretical considerations based on first-principles co...

Nanotechnology gives to the 21st century the “NANO” logo and covers all domains of human activity ranging from electronics and medicine, to aerospace and agriculture. One of the creators of large-scale nanotechnological implementations Mihail Roco, the initiator of the National Nanotechnology Initiative, a United States federal government program, mentioned that “The accelerating pace of discov...