2008/06/03 by Yoji Ohashi, Shunji Tsuchiya · 1 citation
Physics and Astronomy · #Atomic and Subatomic Physics Research #Bose–Einstein condensate #Cold Atom Physics and Bose-Einstein Condensates #Condensed matter physics #Cooper pair #Josephson effect #Phonon #Physics #Quantum mechanics #Quantum tunnelling #Quantum, superfluid, helium dynamics #Superconductivity #Supercurrent #cond-mat.other
paper · pdf · doi:10.1103/physreva.78.043601
22 pages, 3 figures
arxiv created 2008/06/03 · openalex publication_date 2008/10/03 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We investigate tunneling properties of Bogoliubov mode in a Bose-Einstein condensate. Using an exactly solvable model with a \ensuremathδ-functional barrier, we show that each component in the two-component wave function (u,v) of low-energy Bogoliubov phonon has the same form as the condensate wave function in the supercurrent state. As a result, the currents Ju and Jv associated with u and v, respectively, have the same tunneling properties as those of supercurrent carried by condensate. Thus, the tunneling of low-energy Bogoliubov phonon described by the tunneling of these two currents shows perfect transmission. We also show that the supercurrent behaviors of Bogoliubov phonon still exist in the presence of supercurrent carried by condensate, except in the critical supercurrent state. In the critical current state, the perfect transmission is absent, because Ju or Jv exceeds their upper limit given by the critical value of the supercurrent associated with the condensate. Our results consistently explain the recently proposed two tunneling phenomena associated with Bogoliubov phonon, namely, the anomalous tunneling effect (perfect transmission in the low-energy limit) and the breakdown of the perfect transmission in the critical supercurrent state.