aqora

Transporte dependente de spin através de um potencial delta de Dirac acoplado a uma coordenada harmônica

F. C. Penha, Beat Roethlisberger, Daniel Loss +1 more

Caderno de ResumosJan 1, 20110 citations

Propagator calculations for time dependent Dirac delta potentials and corresponding two state models

Swati Mudra, Aniruddha Chakraborty

Physics Letters ASep 29, 20215 citations

Unidirectional spin transport of a spin-orbit-coupled atomic matter wave using a moving Dirac δ -potential well

Jieli Qin, Lu Zhou

We study the transport of a spin-orbit-coupled atomic matter wave using a moving Dirac $\ensuremath{\delta}$-potential well. In a spin-orbit-coupled system, bound states can be formed in both ground and excited energy levels with a Dirac $\ensuremath{\delta}$ potential. Because Galilean invariance is broken in a spin-orbit-coupled system, moving of the potential will induce a velocity-dependent effective detuning. This induced detuning breaks the spin symmetry and makes the ground-state transporting channel be spin-$\ensuremath{\uparrow}$ ($\ensuremath{\downarrow}$) favored while makes the excited-state transporting channel be spin-$\ensuremath{\downarrow}$ ($\ensuremath{\uparrow}$) favored for a positive-direction (negative-direction) transporting. When the $\ensuremath{\delta}$-potential well moves at a small velocity, both the ground-state and the excited-state channels contribute to the transportation, and thus both the spin components can be efficiently transported. However, when the moving velocity of the $\ensuremath{\delta}$-potential well exceeds a critical value, the induced detuning is large enough to eliminate the excited bound state, and makes the ground bound state the only transporting channel, in which only the spin-$\ensuremath{\uparrow}$ ($\ensuremath{\downarrow}$) component can be efficiently transported in a positive (negative) direction. This work demonstrates a prototype of unidirectional spin transport.We study the transport of a spin-orbit-coupled atomic matter wave using a moving Dirac $\ensuremath{\delta}$-potential well. In a spin-orbit-coupled system, bound states can be formed in both ground and excited energy levels with a Dirac $\ensuremath{\delta}$ potential. Because Galilean invariance is broken in a spin-orbit-coupled system, moving of the potential will induce a velocity-dependent effective detuning. This induced detuning breaks the spin symmetry and makes the ground-state transporting channel be spin-$\ensuremath{\uparrow}$ ($\ensuremath{\downarrow}$) favored while makes the excited-state transporting channel be spin-$\ensuremath{\downarrow}$ ($\ensuremath{\uparrow}$) favored for a positive-direction (negative-direction) transporting. When the $\ensuremath{\delta}$-potential well moves at a small velocity, both the ground-state and the excited-state channels contribute to the transportation, and thus both the spin components can be efficiently transported. However, when the moving velocity of the $\ensuremath{\delta}$-potential well exceeds a critical value, the induced detuning is large enough to eliminate the excited bound state, and makes the ground bound state the only transporting channel, in which only the spin-$\ensuremath{\uparrow}$ ($\ensuremath{\downarrow}$) component can be efficiently transported in a positive (negative) direction. This work demonstrates a prototype of unidirectional spin transport.

arXiv:2007.03147Physical Review AJul 6, 20204 citations

An alternative derivation of the spin-dependent quantum potential

Nicola Cufaro Petroni, Ph. Gueret, A. Kypriakidis +1 more

Lettere al nuovo cimento della societa italiana di fisica/Lettere al nuovo cimentoApr 1, 19853 citations

Transport in Heisenberg spin chains

Christian Groß

Bulletin of the American Physical SocietyJun 12, 20150 citations

A parabolic model for dimple potentials

Melike Cibik Aydin, Haydar Uncu, Coşkun Deniz

We study the truncated parabolic function and demonstrate that it is a representation of the Dirac δ function. We also show that the truncated parabolic function, used as a potential in the Schrödinger equation, has the same bound state spectrum, tunneling and reflection amplitudes as the Dirac δ potential, as the width of the parabola approximates to zero. Dirac δ potential is used to model dimple potentials which are utilized to increase the phase-space density of a Bose–Einstein condensate in a harmonic trap. We show that a harmonic trap with a δ function at the origin is a limiting case of the harmonic trap with a symmetric truncated parabolic potential around the origin. Hence, the truncated parabolic is a better candidate for modeling the dimple potentials.We study the truncated parabolic function and demonstrate that it is a representation of the Dirac δ function. We also show that the truncated parabolic function, used as a potential in the Schrödinger equation, has the same bound state spectrum, tunneling and reflection amplitudes as the Dirac δ potential, as the width of the parabola approximates to zero. Dirac δ potential is used to model dimple potentials which are utilized to increase the phase-space density of a Bose–Einstein condensate in a harmonic trap. We show that a harmonic trap with a δ function at the origin is a limiting case of the harmonic trap with a symmetric truncated parabolic potential around the origin. Hence, the truncated parabolic is a better candidate for modeling the dimple potentials.

arXiv:1211.5438Physica ScriptaAug 20, 20133 citations

Spin-dependent transport through a Dirac delta potential coupled to a harmonic coordinate

Related papers

Spin-dependent transport through a Dirac delta potential coupled to a harmonic coordinate

Related papers