Physics - Condensed Matter Seminar

View Full Calendar

Condensed Matter Seminar - "Transport in 1D helical Luttinger liquids in the fractional quantum Hall regime"

Event Type
Seminar/Symposium
Sponsor
Physics - Condensed Matter
Location
ESB 190
Date
Apr 12, 2024   1:00 pm  
Speaker
Leonid Rokhinson, Purdue University
Contact
Stephen Bullwinkel
E-Mail
bullwink@illinois.edu
Phone
217-333-1652
Views
88

Domain walls in fractional quantum Hall ferromagnets are gapless helical one-dimensional channels formed at the boundaries of topologically distinct quantum Hall (QH) liquids. Naïvely, these helical domain walls (hDWs) constitute two counter-propagating chiral states with opposite spins. Coupled to an s-wave superconductor, helical channels are expected to lead to topological superconductivity with high order non-Abelian excitations. Experimental investigation of a transport through a single hDWs in the ν=2/3 fractional QH regime is found to be substantially smaller than the prediction of the naïve model. Luttinger liquid theory of the system reveals redistribution of currents between quasiparticle charge, spin and neutral modes, and predicts the reduction of the hDW current. Inclusion of spin-non-conserving tunneling processes reconciles theory with experiment. The theory confirms emergence of spin modes required for the formation of fractional topological superconductivity.

link for robots only