Preparation of the Spin-Mott State: A Spinful Mott Insulator of Repulsively Bound Pairs

Abstract

We observe and study a special ground state of bosons with two spin states in an optical lattice: the spin-Mott insulator, a state that consists of repulsively bound pairs that is insulating for both spin and charge transport. Because of the pairing gap created by the interaction anisotropy, it can be prepared with low entropy and can serve as a starting point for adiabatic state preparation. We find that the stability of the spin-Mott state depends on the pairing energy, and observe two qualitatively different decay regimes, one of which exhibits protection by the gap.

Atomic physics on a 50-nm scale: Realization of a bilayer system of dipolar atoms

“…Furthermore, with a magnetic dipole moment of only 1 μ B , the dipolar interaction for alkali atoms is 100 times weaker than for Dy. Therefore, previous work on alkalis has used spin-dependent forces to control the overlap between sites with spin up and down ( 27 , 33 ) but not to study interactions between nonoverlapping sites.…”

Bose-Einstein condensates with Raman-induced spin-orbit coupling: An overview

“…Alternatively, one can consider a quasi-two-dimensional setup with reduced spatial overlap of the two spin components along the strongly confined direction. This can be achieved through a properly chosen spin-dependent trapping potential [70][71][72] or using pseudospin orbital states in a superlattice [73]. The latter method was employed in the work [66] by Ketterle's group at MIT, which reported on the first observation of the density fringes in the stripe phase through Bragg measurements; in the same experiment it was also verified that an higher miscibility enhances the stability of the stripe phase against magnetic field fluctuations [71].…”

Atomic physics on a 50 nm scale: Realization of a bilayer system of dipolar atoms

“…This is the main new concept of our scheme. Spin-dependent potentials have been realized with rubidium (Rb) [25][26][27][28][29] and cesium (Cs) [22,30]. However, strong spin-dependent potentials for alkali atoms require near-resonant light with detunings smaller than the fine-structure splitting ∆ FS , causing severe heating due to spontaneous emission.…”

“…Furthermore, with a magnetic dipole moment of only 1 µ B , the dipolar interaction for alkali atoms is 100 times weaker than for Dy. Therefore, previous work on alkalis has used spin-dependent forces to control the overlap between sites with spin up and down [22,28], but not to study interactions between non-overlapping sites.…”

“…This is the situation when the σ + and the σ − standing waves are created by retro-reflecting a single beam in the lin-ϑ-lin geometry, as often used for alkalis (e.g. [25,26,28]). For Dy, the Raman couplings induce tunneling and they weaken the potential minima when their separation becomes smaller than λ/10, where λ is the wavelength of the light.…”