Weak localization and crossover from Lifshitz transition in two dimensions

This article describes a series of experiments, mostly performed by the author and his collaborators over a period of 15 years, attempting to understand with the increase of disorder, the evolution from a Fermi liquid, to a state of localized electrons. During this period we relied heavily on theoretical advances, and the experiments were designed to test those theoretical models and challenge them in the regime of a highly correlated system. Experimentally, we were able to continuously tune through this regime into the insulating state and this allows measurements all the way from weak localization in two dimensions to strong localization and the insulating state. My efforts were focused mainly on electron transport and tunneling and will be described in this article. For this author, the work of my colleagues (and myself) during this period changed the way I think about electron transport.

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Crossover of level statistics between strong and weak localization in two dimensions

EPL (Europhysics Letters) ◽

10.1209/epl/i1996-00499-9 ◽

1996 ◽

Vol 34 (8) ◽

pp. 587-592 ◽

Cited By ~ 21

Author(s):

I. Kh Zharekeshev ◽

M Batsch ◽

B Kramer

Keyword(s):

Weak Localization ◽

Two Dimensions ◽

Level Statistics

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SCALING OF RESISTANCE IN THE TWO-DIMENSIONAL ANDERSON TIGHT-BINDING MODEL OF DISORDERED SYSTEMS II

Modern Physics Letters B ◽

10.1142/s0217984994000212 ◽

1994 ◽

Vol 08 (03) ◽

pp. 195-203 ◽

Cited By ~ 4

Author(s):

ANIRBAN SAIN ◽

ABHIJIT MOOKERJEE

Keyword(s):

Disordered Systems ◽

Tight Binding ◽

Weak Localization ◽

Real Space ◽

Two Dimensions ◽

Localized States ◽

Two Dimensional ◽

Binding Model ◽

Algebraic Decay ◽

Band Center

Several workers using different numerical methods have in recent times obtained algebraic decay of wave function amplitudes for localized states at the band center of a two-dimensional disordered system. These include vector recursion,1 direct diagonalization,2 and real space renormalization techniques.3 We modify a version of the combined real space renormalization and vector recursion techniques, including the effect of the random environment on the phase differences between the electronic incoming waves through the different incoming leads, to confirm the algebraic or weak localization at the band center of a random tight-binding Anderson model in two dimensions.

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The tangled web of agency

Behavioral and Brain Sciences ◽

10.1017/s0140525x17001170 ◽

2018 ◽

Vol 41 ◽

Author(s):

Alain Pe-Curto ◽

Julien A. Deonna ◽

David Sander

Keyword(s):

Two Dimensions ◽

Bad Company

AbstractWe characterize Doris's anti-reflectivist, collaborativist, valuational theory along two dimensions. The first dimension is socialentanglement, according to which cognition, agency, and selves are socially embedded. The second dimension isdisentanglement, the valuational element of the theory that licenses the anchoring of agency and responsibility in distinct actors. We then present an issue for the account: theproblem of bad company.

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A transmission electron microscopic study of structural transitions in fast ionic conductors

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100125713 ◽

1987 ◽

Vol 45 ◽

pp. 156-157

Author(s):

R. B. Queenan ◽

P. K. Davies

Keyword(s):

Optical Properties ◽

Ionic Conduction ◽

Recent Observation ◽

Ionic Conductivities ◽

Sodium Aluminate ◽

Two Dimensions ◽

Ionic Conductors ◽

Electron Microscopic ◽

Transmission Electron ◽

Trivalent Cations

Na ß“-alumina (Na1.67Mg67Al10.33O17) is a non-stoichiometric sodium aluminate which exhibits fast ionic conduction of the Na+ ions in two dimensions. The Na+ ions can be exchanged with a variety of mono-, di-, and trivalent cations. The resulting exchanged materials also show high ionic conductivities.Considerable interest in the Na+-Nd3+-ß“-aluminas has been generated as a result of the recent observation of lasing in the pulsed and cw modes. A recent TEM investigation on a 100% exchanged Nd ß“-alumina sample found evidence for the intergrowth of two different structure types. Microdiffraction revealed an ordered phase coexisting with an apparently disordered phase, in which the cations are completely randomized in two dimensions. If an order-disorder transition is present then the cooling rates would be expected to affect the microstructures of these materials which may in turn affect the optical properties. The purpose of this work was to investigate the affect of thermal treatments upon the micro-structural and optical properties of these materials.

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