Science Daily December 23, 2020
Tunneling plays an essential role in many branches of physics and has found important applications. It is theoretically proposed that Klein tunneling occurs when, under normal incidence, quasiparticles exhibit unimpeded penetration through potential barriers independent of their height and width. A team of researchers in the US (UC Berkeley, Georgia Institute of Technology, Lawrence Berkeley National Laboratory) created a phononic heterojunction by sandwiching two types of artificial phononic crystals with different Dirac point energies. They demonstrated direct observation of Klein tunneling as shown by the key feature of unity transmission. Their experiment reveals that Klein tunneling occurs over a broad band of acoustic frequency. The findings could find applications in signal processing, biomedical devices, super collimated beams, and communications…read more. TECHNICAL ARTICLE