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Local electrostatic imaging of striped domain order in LaAlO3/SrTiO3.
This work uses a scanning charge detector--a nanotube single-electron transistor--to non-invasively image the electrostatic landscape and local mechanical response in the prototypical LaAlO3/SrTiO3 system with unprecedented sensitivity, revealing large anomalous piezoelectricity with curious spatial dependence on microscopic scales.
Noise characteristics of 100 nm scale GaAs/Al x Ga 1x As scanning Hall probes
Magnetic imaging techniques are useful for studying systems with magnetic features at microscopic length scales. Magnetic force microscopy offers the highest spatial resolution currently achievable
Mapping the twist-angle disorder and Landau levels in magic-angle graphene
The importance of θ disorder as an unconventional type of disorder enabling the use of twist-angle gradients for bandstructure engineering, for realization of correlated phenomena and for gate-tunable built-in planar electric fields for device applications is established.
A scanning superconducting quantum interference device with single electron spin sensitivity.
It is shown that nanoscale SQUIDs with diameters as small as 46 nm can be fabricated on the apex of a sharp tip, and they can operate over a wide range of magnetic fields, providing a sensitivity of 0.6 μB Hz(-1/2) at 1 T.
Steady-state photocarrier grating technique for diffusion length measurement in photoconductive insulators
A new simple technique for the determination of the diffusion length in photoconductive insulators is presented. A steady‐state photocarrier grating is created by two interfering laser beams, and the
Imaging of super-fast dynamics and flow instabilities of superconducting vortices
A unique scanning microscopy technique is used to image steady-state penetration of super-fast vortices into a superconducting Pb film at rates of tens of GHz and velocities up to tens of km/s, offering an insight into the fundamental physics of dynamic vortex states of superconductors at high current densities.
Flux creep characteristics in high‐temperature superconductors
We describe the voltage‐current characteristics of YBa2Cu3O7−δ epitaxial films within the flux creep model in a manner consistent with the resistive transition behavior. The magnitude of the
Probing dynamics and pinning of single vortices in superconductors at nanometer scales
The fundamental dependence of the elementary pinning force of multiple defects on the vortex displacement is measured, for the first time, revealing a far more complex behavior than has previously been recognized, including striking spring softening and broken-spring depinning, as well as spontaneous hysteretic switching between cellular vortex trajectories.
Measurement of the stray field emanating from magnetic force microscope tips by Hall effect microsensors
We describe the use of micronic Hall sensors as magnetic-field profilometers with submicron resolution. The procedure involves the deconvolution of Hall voltage maps produced by scanning the field
Steady‐state photocarrier grating technique for diffusion‐length measurement in semiconductors: Theory and experimental results for amorphous silicon and semi‐insulating GaAs
The theory underlying the steady‐state photocarrier grating technique is presented, including the effect of surface recombination. Experimental results for amorphous hydrogenated silicon and