Observation of 2D Mott insulator and $π$ -superfluid quantum phase transition in shaking optical latticeObservation of 2D Mott insulator and $π$-superfluid quantum phase transition in shaking optical lattice

Jingxin Sun, Pengju Zhao, Zhongshu Hu +4 more

The Mott insulator and superfluid phase transition is one of the most prominent phenomena in ultracold atoms. In this work, we report the observation of a novel 2D quantum phase transition between Mott insulator and $π$ superfluid in a shaking optical lattice. In the deep optical lattice regime, the lowest $s$ -band can be tuned to Mott phase, while the higher $p_{x,y}$ bands are itinerant for having larger bandwidth. Through a shaking technique coupling the $s$ orbital to $p_{x,y}$ orbital states, we experimentally observe the transition between the states of the $s$ and $p_{x,y}$ bands, leading to a quantum phase transition from 2D $s$ -orbital Mott phase to the $p_{x,y}$ -orbital superfluid which condensed at $(π,π)$ momentum.The Mott insulator and superfluid phase transition is one of the most prominent phenomena in ultracold atoms. In this work, we report the observation of a novel 2D quantum phase transition between Mott insulator and $π$ superfluid in a shaking optical lattice. In the deep optical lattice regime, the lowest $s$-band can be tuned to Mott phase, while the higher $p_{x,y}$ bands are itinerant for having larger bandwidth. Through a shaking technique coupling the $s$ orbital to $p_{x,y}$ orbital states, we experimentally observe the transition between the states of the $s$ and $p_{x,y}$ bands, leading to a quantum phase transition from 2D $s$-orbital Mott phase to the $p_{x,y}$-orbital superfluid which condensed at $(π,π)$ momentum.

arXiv:2306.04477Jun 7, 20230 citations

Superfluid-Mott-Insulator Transition

Manuel Endres

Springer thesesJan 1, 20142 citations

A comparison of trapping the rubidium atoms in optical and magnetic lattices

Parvin Karimi, Saeed Ghanbari, Fatemeh Rezaei

Abstract In this paper, the critical parameters of quantum phase transition from the superfluid to the Mott insulator phase are studied for three-dimensional traps in 2D optical lattices and permanent magnetic lattices for trapping the 87 Rb atoms. Using the harmonic oscillator wave function approximation, the on-site interaction U , the hopping matrix element J and the ratio J / U are calculated to determine the quantum phase transition point analytically. In a magnetic lattice two components of the external magnetic field B 1 x and B 1 y had been considered for studying quantum phase transition. Here, B 1 z as the z - direction component of the bias magnetic field is also considered for further control of the magnetic lattice parameters. In addition, an optical lattice constructed from the interference of two pairs of orthogonal counter-propagating laser beams is investigated. In both optical and magnetic lattices, the ratio J / U and the critical point of the quantum phase transition can be calculated by variation of the potential barrier height between traps. Comparison of optical lattices with permanent magnetic lattices shows that in the critical point of quantum phase transition the potential barrier height of the magnetic potential is higher than that of the optical trap which suggests that the magnetic microtraps are deeper and more stable than the optical traps in similar structures.Abstract In this paper, the critical parameters of quantum phase transition from the superfluid to the Mott insulator phase are studied for three-dimensional traps in 2D optical lattices and permanent magnetic lattices for trapping the 87 Rb atoms. Using the harmonic oscillator wave function approximation, the on-site interaction U , the hopping matrix element J and the ratio J / U are calculated to determine the quantum phase transition point analytically. In a magnetic lattice two components of the external magnetic field B 1 x and B 1 y had been considered for studying quantum phase transition. Here, B 1 z as the z - direction component of the bias magnetic field is also considered for further control of the magnetic lattice parameters. In addition, an optical lattice constructed from the interference of two pairs of orthogonal counter-propagating laser beams is investigated. In both optical and magnetic lattices, the ratio J / U and the critical point of the quantum phase transition can be calculated by variation of the potential barrier height between traps. Comparison of optical lattices with permanent magnetic lattices shows that in the critical point of quantum phase transition the potential barrier height of the magnetic potential is higher than that of the optical trap which suggests that the magnetic microtraps are deeper and more stable than the optical traps in similar structures.

Physica ScriptaMar 25, 20212 citations

A new class of permanent magnetic lattices for ultracold atoms and Bose-Einstein condensates

Saeed Ghanbari, Tien D. Kieu, Peter Hannaford

We propose a new class of permanent magnetic lattices on an atom chip for producing 1D and 2D periodic arrays of Ioffe-Pritchard magnetic micro-traps with variable barrier height for trapping and manipulating ultracold atoms and Bose-Einstein condensates. The barrier height of the microtraps may be varied by changing a bias magnetic field. In one of the con gurations, we show how we can go from a 1D array of 2D microtraps to a 2D array of 3D microtraps by changing the angle between two crossed arrays of parallel rectangular magnets. Furthermore, by changing the angle between the crossed arrays of magnets, the barrier heights can be varied. This suggests the possibility of performing a type of 'mechanical' BEC to Mott insulator quantum phase transition in a permanent magnetic lattice.We propose a new class of permanent magnetic lattices on an atom chip for producing 1D and 2D periodic arrays of Ioffe-Pritchard magnetic micro-traps with variable barrier height for trapping and manipulating ultracold atoms and Bose-Einstein condensates. The barrier height of the microtraps may be varied by changing a bias magnetic field. In one of the con gurations, we show how we can go from a 1D array of 2D microtraps to a 2D array of 3D microtraps by changing the angle between two crossed arrays of parallel rectangular magnets. Furthermore, by changing the angle between the crossed arrays of magnets, the barrier heights can be varied. This suggests the possibility of performing a type of 'mechanical' BEC to Mott insulator quantum phase transition in a permanent magnetic lattice.

Jan 1, 20060 citations

Quantum phase transition from a superfluid to a Mott insulator in an ultracold gas of atoms

Markus Greiner, Olaf Mandel, Tim Rom +4 more

Physica B Condensed MatterMay 1, 200317 citations

Observation of 2D Mott insulator and

π

-superfluid quantum phase transition in shaking optical lattice

π

superfluid in a shaking optical lattice. In the deep optical lattice regime, the lowest

s

-band can be tuned to Mott phase, while the higher

p_{x,y}

bands are itinerant for having larger bandwidth. Through a shaking technique coupling the

s

orbital to

p_{x,y}

orbital states, we experimentally observe the transition between the states of the

s

and

p_{x,y}

bands, leading to a quantum phase transition from 2D

s

-orbital Mott phase to the

p_{x,y}

-orbital superfluid which condensed at

(π,π)

momentum.