Figure 1: Scheme of experiment and and entropy in perpendicular magnetic field.
From: Strongly correlated two-dimensional plasma explored from entropy measurements
(a) Experimental set-up, schematic cross-section, and energy band diagram of the Si-MOSFET structure. (b,c) The density of states for a 2D electron gas in quantizing magnetic field versus energy and electron density, respectively. Green colour denotes filled states. (d,e) Ratios S/T and T−1∂S/∂n versus electron density for different relationships between Γ, T and ℏωc (shown in the figure). (f–h) The entropy per electron at T=3 K versus magnetic field measured with three samples ((f) Si8-9, (g) Si-UW1, and (h) GaAs1). The upper axis (filling factor ν=eB/(hn) ) is common for all the three panels. The densities are shown on the panels. Cyan curves represent the fit using the noninteracting electron gas model with the band effective masses and level broadenings indicated on the panels. (i) ∂S/∂n versus density measured at 9 T with Si-UW2. The temperatures are shown on the panel. Hatched regions S1 and S2 have approximately the same area (see text). The data spread for each density at 2.5 K indicate typical noise level. (j) Normalized entropy versus density for the same sample.
