Coherent zero-field magnetization resonance in a dipolar spin-1 Bose-Einstein condensate

Abstract

With current magnetic field shielding and high precision detection in dipolar spinor Bose-Einstein condensates, it is possible to experimentally detect the low or zero field nonsecular dipolar dynamics. Here we analytically investigate the zero-field nonsecular magnetic dipolar interaction effect, with an emphasis on magnetization dynamics in a spin-1 Bose-Einstein condensate under the single spatial mode approximation within the mean field theory. Due to the biaxial nature of the dipolar interaction, a novel resonance occurs in the condensate magnetization oscillation, contrast to the previous assumption of a conserved magnetization in strong magnetic fields. Furthermore, we propose a dynamical-decoupling detection method for such a resonance, which cancels the stray magnetic fields in experiments but restores the magnetization dynamics. Our results shed new lights on the dipolar systems and may find potential applications beyond cold atoms.

Magnetic-field-induced dynamical instabilities in an antiferromagnetic spin-1 Bose-Einstein condensate

“…Quantum systems may exhibit various types DIs, in particular, in Bose-Einstein condensates (BECs), which are generally described by the Gross-Pitaevskii equation or nonlinear Schrödinger equation within the mean * Corresponding email: wxzhang@whu.edu.cn field theory [9,10]. The fine tunability and the wonderful controllability in BEC experiments provide an excellent testbed for many theoretical predictions [11][12][13][14][15][16][17][18]. In fact, the DIs exist not only in scalar (single-component) BECs, such as solitons [19] and vortices [20], but also in spinor BECs, including the two-component and threecomponent spinor BECs, where vector solitons [21], Skyrmion vortices [22,23], and spin domains/textures are explored [24][25][26][27][28][29][30].…”

“…The fine tunability and the wonderful controllability in BEC experiments provide an excellent testbed for many theoretical predictions [11][12][13][14][15][16][17][18]. In fact, the DIs exist not only in scalar (single-component) BECs, such as solitons [19] and vortices [20], but also in spinor BECs, including the two-component and threecomponent spinor BECs, where vector solitons [21], Skyrmion vortices [22,23], and spin domains/textures are explored [24][25][26][27][28][29][30].…”

Rebuilding of destroyed spin squeezing in noisy environments

“…We consider a 87 Rb ferromagnetic spin-1 condensate, where c 2 < 0, c 0 ≫ |c 2 | and c d ≤ 0.1|c 2 |, and the single mode approximation is valid in a small or medium magnetic field [31][32][33] . Under this single mode approximation 26,31 ,Ψ α (r r r) ≃ φ (r r r)â α with φ (r r r) being a spin-independent spatial mode function andâ α the annihilation operator of spin component α.…”

Critically-enhanced spin-nematic squeezing and entanglement in dipolar spinor condensates

“…In spinor atomic BECs, besides nonlinear collisional interactions, there is also long-range magnetic dipole-dipole interaction (MDDI) [26][27][28][29][30][31][32][33][34][35]. According to the recent exper-imental and theoretical observation in 23 Na, 87 Rb and 52 Cr atoms, the MDDIs are indeed not negligible for these spinor condensates.…”