Detection of interaction-induced nonlocal effects using perfectly transmitting nanostructures

Abstract

PACS 73.23.-b -Electronic transport in mesoscopic systems PACS 71.10.-w -Theories and models of many-electron systems PACS 73.63.Nm -Quantum wiresAbstract. -We consider one-dimensional transport through an interacting region in series with a point-like one-body scatterer. When the conductance of the interacting region is perfect, independently of the interaction strength, a nonlocal interaction effect yields a total conductance of the composed system that depends on the interaction strength and is lower than the transmission of the one-body scatterer. This qualitative nonlocal effect allows to probe the dressing cloud of an interacting system by ideal noninteracting leads. The conductance correction increases with the strength of the interaction and the reflection of the one-body scatterer (attaining relative changes > 50%), and decreases with the distance between the interacting region and the one-body scatterer. Scaling laws are obtained and possible experimental realizations are suggested. p-6

Theory of scanning gate microscopy

“…This effect, different from the cross talk between the tip and the gates defining the structure, 7 has been treated in one-dimensional lattice models in Ref. 55.…”

What Is Measured in the Scanning Gate Microscopy of a Quantum Point Contact?

“…This paradigm exhibiting conductance quantization [12][13][14][15][16] has been well studied by SGM [1][2][3][4]. In addition, recent work suggests the relevance of this powerful technique for probing the nonlocality of electronic interactions [17][18][19].The scattering theory of quantum conductance [20,21] assumes that the leads are disorder-free, confined in the transverse (y) direction, and semi-infinite in the longitudinal (x) direction. The electron states in the leads are products of quantized transverse wavefunctions φ a (y) labeled by the index a with transverse energy ε (t) a and plane waves propagating in the x direction with wavevector magnitudes k a .…”

“…This paradigm exhibiting conductance quantization [12][13][14][15][16] has been well studied by SGM [1][2][3][4]. In addition, recent work suggests the relevance of this powerful technique for probing the nonlocality of electronic interactions [17][18][19].…”

Scattering approach to scanning gate microscopy

“…These oscillations can be explained by the interference between two kinds of electron trajectories that lead to scattering back into the narrow channel: reection at the narrow-wide interface and reection by the tip. Such oscillations appear in theoretical approaches and in many SGM experiments on quantum point contact structures (see for example [29,13,2,3,30,31]). Recently, deviations from that periodicity have been observed [32], and the modications expected in a parallel magnetic eld have been calculated [33].…”