Mott insulating phase

It is possible to create an atomic Mott insulator phase in an optical lattice, in which sites in a given region are occupied by a specific integer number of atoms [98], A lattice with two atoms per site is ideal for making diatomic molecules by PA (or MA) and protecting them from collisions in a sense, PA is then converted from a free -> bound process to a bound -> bound process, because the two atoms are confined in the lattice site. Homonuclear and heteronuclear diatomic molecule formation in this and other ways has been proposed ([99] and [100], respectively) and more recently observed ([101-104] and [67,105], respectively). 

The switching or memory phenomena induced by electric field application or photo irradiation have been studied on Mott insulators, charge ordered insulators, and N-I transition systems and were found to be fast phase transitions in general. For the former two systems, the phase transitions caused a pronounced change in reflectance and conductivity from insulating to metallic features. The third system also exhibited a change in conductivity and dielectric response connected with the transports of solitons and/or domain walls, dynamic dimerization, and... 

An alternative way to clarify the nature of this state is to test its stability with respect to a metal-insulator transition. This has received a lot of theoretical attention recently. The JT singlet ground state makes these compounds free from the tendency towards a magnetic instability observed in so many Mott insulators. In fact, their ground state does not break any symmetry and Capone et al. explained [43] that it then has a zero entropy, which makes a direct connection with a metal impossible (it would violate the Luttinger theorem). These authors predict that the only way to go from the insulator to the metal would be through an exotic superconducting phase or a first-order transition. 

N. F. Mott, Metal-Insulator Phase Transitions, Taylor and Francis, London, 1974. 

The electronic structure of bulk V2O3 has been studied by different theoretical methods [106-109]. The main goal was to explain the physics of the Mott transition at Tc= 150 - 170K where the material transforms from an antiferromagnetic insulating phase with monoclinic structure below Tc to a paramagnetic... 

M. Greiner, O. Mandel, T. EssUnger, T.W Hansch, I. Bloch, Quantum phase transition from a superfluid to a Mott insulator in a gas of ultracold atoms. Nature 415(6867), 39-44 (2(X)2). doi 10.1038/415039a... 

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