摘要: Submillimeter-wave and far-infrared conductivities of MgB2 have been investigated using different experimental techniques. The data provide clear evidence for the onset a superconducting gap at 24 cm−1 T = 5K. On increasing temperature energy increases, contrary to what is expected in isotropic BCS superconductors. small zero-temperature value its unconventional increase on can be explained by highly anisotropic or multiple function. A peak temperature-dependent conductivity observed low frequencies, which qualitatively resembles coherence predicted BCS-theory.
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