Supercurrent behavior of low-energy Bogoliubov phonon and anomalous tunneling effect in a Bose-Einstein condensate

Abstract

We investigate tunneling properties of Bogoliubov mode in a Bose-Einstein condensate. Using an exactly solvable model with a delta-functional barrier, we show that each component in the two-component wavefunction (u,v) of low-energy Bogoliubov phonon has the same form as the condensate wavefunction in the supercurrent state. As a result, the currents J_u and J_v 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 J_u or J_v 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.

arXiv comment22 pages, 3 figures

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Cited by in corpus (11)

• Absence of Anomalous Tunneling of Bogoliubov Excitations for Arbitrary Potential Barrier under the Critical Condensate Current
• Fano resonance through Higgs bound states in tunneling of Nambu-Goldstone modes
• Tunneling properties of Bogoliubov mode and spin wave modes in supercurrent states of a spin-1 ferromagnetic spinor Bose-Einstein condensate
• Supercurrent induced by tunneling Bogoliubov excitations in a Bose-Einstein condensate
• Transmission of Excitations in a Spin-1 Bose-Einstein Condensate through a Barrier
• Anomalous tunneling of collective excitations and effects of superflow in the polar phase of a spin-1 spinor Bose-Einstein condensate
• Transmission and Reflection of Collective Modes in Spin-1 Bose-Einstein Condensate
• Exact Results for Tunneling Problems of Bogoliubov Excitations in the Critical Supercurrent State
• Stability Criterion for Superfluidity based on the Density Spectral Function
• Anomalous Scattering of Low-lying Excitations in a Spin-1 Bose-Einstein Condensate
• Perfect transmission and perfect reflection of Bogoliubov quasiparticles in a dynamically unstable Bose-Einstein condensate