Pascal conductance series in ballistic one-dimensional LaAlO$_3$/SrTiO$_3$ channels

TL;DR

This paper reports the experimental discovery of quantized conductance steps following Pascal's triangle in strongly interacting electron waveguides at LaAlO$_3$/SrTiO$_3$ interfaces, indicating new degenerate quantum liquids.

Contribution

The study presents the first observation of Pascal's triangle conductance series in ballistic 1D channels, revealing novel degenerate quantum states in oxide interfaces.

Findings

Quantized conductance steps follow Pascal's triangle sequence.

Robustness of steps against magnetic field and gate voltage.

Evidence of new degenerate quantum liquids from bound electron states.

Abstract

The ability to create and investigate composite fermionic phases opens new avenues for the investigation of strongly correlated quantum matter. We report the experimental observation of a series of quantized conductance steps within strongly interacting electron waveguides formed at the LaAlO$_3$/SrTiO$_3$ interface. The waveguide conductance follows a characteristic sequence within Pascal's triangle: $(1, 3, 6, 10, 15, ...)\cdot e^2/h$, where $e$ is the electron charge and $h$ is the Planck constant. The robustness of these steps with respect to magnetic field and gate voltage indicate the formation of a new family of degenerate quantum liquids formed from bound states of $n = 2, 3, 4, ...$ electrons. These experiments could provide solid-state analogues for a wide range of composite fermionic phases ranging from neutron stars to solid-state materials to quark-gluon plasmas.