Spin and Charge Phases in 1D Electrons

Transverse Electron Focusing (TEF) employs classical and quantum physics for exploring characteristics of one-dimensional (1D) systems [1]. Recently fractional conductance quantisation was reported within 1D channels [2], which appear to arise from a combination of possible spin and charge phases. In the present work, we aim to explore the characteristics of quantized 1D conductance features, particularly those which appear in the ground state due to many body interactions, using TEF. We used devices based on GaAs/AlGaAs heterostructures, where a set of gate combinations in the form of split-gate, top-gate were used to define 1D quantum wires to act as the injector and detector for TEF measurements. We observe the formation of conductance plateaus below e²/h and investigate how these can be imaged using TEF. The TEF spectrum shows a split in the odd focusing peaks, which suggests the fractional states may be spin polarised [1]. Furthermore, we will show results based on TEF including the effect of in-plane magnetic field as well as the effect of change in carrier concentration particularly in the weakly confined regime where the 1D electrons form a zigzag assembly [3].