Long-range influence of manipulating disordered-insulators locally

Abstract

Localization of wavefunctions is arguably the most familiar effect of disorder in quantum systems. It has been recently argued [[V. Khemani, R. Nandkishore, and S. L. Sondhi, Nature Physics, 11, 560 (2015)] that, contrary to naive expectation, manipulation of a localized-site in the disordered medium may produce a disturbance over a length-scale much larger than the localization-length $\xi$. Here we report on the observation of this nonlocal phenomenon in electronic transport experiment. Being a wave property, visibility of this effect hinges upon quantum-coherence, and its spatial-scale may be ultimately limited by the phase-coherent length of the disordered insulator. Evidence for quantum coherence in the Anderson-insulating phase may be obtained from magneto-resistance measurements which however are useful mainly in thin-films. The technique used in this work offers an empirical method to measure this fundamental aspect of Anderson-insulators even in relatively thick samples.

References in corpus (7)

• Direct observation of Anderson localization of matter-waves in a controlled disorder
• Localization of ultrasound in a three-dimensional elastic network
• Spin relaxation of localized electrons in n-type semiconductors
• Suppression of inelastic electron-electron scattering in Anderson Insulators
• Slow Dynamics of the Electron-Glasses; the Role of Disorder
• Electron Glass in a three-dimensional system
• Optical excitation of Electron-Glasses

Cited by in corpus (3)

• Suppressing quantum effects by optically driven nonequilibrium phonons
• Fluctuation driven transitions in localized insulators: Intermittent metallicity and path chaos precede delocalization
• Onset of nonequilibrium in a driven Anderson insulator