Spatially inhomogeneous electron state deep in the extreme quantum limit of strontium titanate
Anand Bhattacharya, Brian Skinner, Guru S. Khalsa, Alexey V. Suslov
When an electronic system is subjected to a suffciently strong magnetic field that the cyclotron energy is larger than the Fermi energy, the system enters the \extreme quantum limit" (EQL) and becomes susceptible to a number of instabilities. Bringing a three-dimensional electronic system deeply into the EQL can be very difficult, however, since it requires a small Fermi energy, large magnetic field, and low disorder. Here we present an experimental study of the EQL in lightly doped single crystals of strontium titanate, which remain good bulk conductors down to very low temperatures and high magnetic fields. Our experiments probe deeply into the regime where theory has long predicted electron-electron interactions to drive the system into a charge density wave or Wigner crystal type state. A number of interesting features arise in the transport in this regime, including a striking nonlinearity in the current-voltage characteristics. We discuss these features in the context of possible correlated electron states, and present an alternative picture based on magnetic-field induced puddling of electrons.
, Skinner, B.
, Khalsa, G.
and Suslov, A.
Spatially inhomogeneous electron state deep in the extreme quantum limit of strontium titanate, Nature Communications, [online], https://doi.org/10.1038/ncomms12974, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=919402
(Accessed November 29, 2023)