相关论文: Parametric tuning of quantum phase transitions in …
Chemical reactions at ultracold temperature provide an ideal platform to study chemical reactivity at the fundamental level, and to understand how chemical reactions are governed by quantum mechanics. Recent years have witnessed the…
In an atomic gas near a Feshbach resonance, the energy of two colliding atoms is close to the energy of a bound state, i.e., a molecular state, in a closed channel that is coupled to the incoming open channel. Due to the different spin…
A second-order quantum phase transition in two-species Bose-Einstein condensates of 87Rb atoms coupled by a quantized radiant field is revealed explicitly in terms of the energy spectrum which is obtained in the thermodynamic limit and is…
Experimental studies with ultracold atoms have enabled major breakthroughs in understanding three-body physics, historically a fundamental yet challenging problem. This is because the interactions among ultracold atoms can be precisely…
The dipole-coupled two-level atoms(qubits) in a single-mode resonant cavity is studied by extended bosonic coherent states. The numerically exact solution is presented. For finite systems, the first-order quantum phase transitions occur at…
Phase transition between ferroelectricity and quantum paraelectricity via non-thermal tuning parameters can lead to quantum critical behavior and associated emergent phenomena. Ferroelectric quantum critical systems are, however, rare…
We study a quantum Bose-Fermi mixture near a broad Feshbach resonance at zero temperature. Within a quantum field theoretical model a two-step Gaussian approximation allows to capture the main features of the quantum phase diagram. We show…
We address the finite temperature phase diagram of ultracold fermionic atoms across a Feshbach resonance based on a functional integral for an atom-molecule model. This allows to fully exploit the presence of the global symmetry of phase…
Quantum interference effects in inter-conversion between cold atoms and diatomic molecules are analysed. Within the framework of Fano's theory, continuum-bound anisotropic dressed state formalism of atom-molecule quantum dynamics is…
We show that the essential properties of a Feshbach resonance in cold atomic gases can be tuned by dressing the atomic states in different scattering channels through inter-channel couplings. Such a scheme can be readily implemented in the…
We investigate the Feshbach conversion of fermion atomic pairs to condensed boson molecules with a microscopic model that accounts the repulsive interactions among all the particles involved. We find that the conversion efficiency is…
We study bosonic atoms near a Feshbach resonance, and predict that in addition to a standard normal and atomic superfluid phases, this system generically exhibits a distinct phase of matter: a molecular superfluid, where molecules are…
We study the quantum phase transition between a normal Bose superfluid to one that breaks additional Z_2 Ising symmetry. Using the recent shaken optical lattice experiment as an example, we first show that at mean-field level atomic…
Tunable scattering resonances are crucial for controlling atomic and molecular systems. However, their use has so far been limited to ultracold temperatures. These conditions remain hard to achieve for most hybrid trapped ion-atom systems…
By using worldline and diagrammatic quantum Monte Carlo techniques, matrix product state and a variational approach \`a la Feynman, we investigate the equilibrium properties and relaxation features of a quantum system of $N$ spins…
Phase transitions which occur at zero temperature when some non-thermal parameter like pressure, chemical composition or magnetic field is changed are called quantum phase transitions. They are caused by quantum fluctuations which are a…
As the temperature of a many-body system approaches absolute zero, thermal fluctuations of observables cease and quantum fluctuations dominate. Competition between different energies, such as kinetic energy, interactions or thermodynamic…
We present a comprehensive collection of ultracold three-body collisions properties near overlapping Feshbach resonances. Our results incorporate variations of all scattering lengths and demonstrate novel collisional behavior, such as…
We consider the magnetically tunable Feshbach resonances that may exist in ultracold mixtures of molecules in $^2\Sigma$ states and alkali-metal atoms. We focus on Rb+CaF as a prototype system. There are likely to be Feshbach resonances…
A central quantity of importance for ultracold atoms is contact, which measures two-body correlations at short distances in dilute systems. It appears in universal relations among thermodynamic quantities, such as large momentum tails,…