Cooling Low-Dimensional Electron Systems into the Microkelvin Regime

Lev Levitin, Harriet van der Vliet, Terje Theisen, Stefanos Dimitriadis, Marijn Lucas, Antonio Corcoles-Gonzalez, Jan Nyeki, Andrew Casey, Graham Creeth, Ian Farrer, Dave Ritchie, James Nicholls, John Saunders

Research output: Contribution to journalArticlepeer-review

Abstract

Two-dimensional electron gases (2DEGs) with high mobility, engineered in semiconductor heterostructures host a variety of ordered phases arising from strong correlations, which emerge at sufficiently low temperatures. The 2DEG can be further controlled by surface gates to create quasi-one dimensional systems, with potential spintronic applications. Here we address the long-standing challenge of cooling such electrons to below 1 mK, potentially important for identification of topological phases and spin correlated states. The 2DEG device was immersed in liquid 3 He, cooled by the nuclear adiabatic demagnetization of copper. The temperature of the 2D electrons was in-
ferred from the electronic noise in a gold wire, connected to the 2DEG by a metallic ohmic contact. With effective screening and filtering, we demonstrate a temperature of 0.9 ± 0.1 mK, with scope for significant further improvement. This platform is a key technological step, paving the way to observing new quantum phenomena, and developing new generations of nanoelectronic devices exploiting correlated electron states.
Original languageEnglish
Article number667
JournalNature Communications
Volume13
DOIs
Publication statusPublished - 3 Feb 2022

Cite this