Phonon-Induced Resistance Oscillations in 2D Systems with a Very High Electron Mobility

We report on the temperature dependence of acoustic-phonon-induced resistance oscillations in very-high mobility two-dimensional electron systems. We observe that the temperature dependence is nonmonotonic and that higher order oscillations are best developed at progressively lower temperatures. Our analysis shows that, in contrast with the Shubnikov–de Haas effect, phonon-induced resistance oscillations are sensitive to electron-electron interactions modifying the single particle lifetime.

Figure 1

(a) Magnetoresistivity $\rho$ at $T=3.5\mathrm{K}$ showing up to eight PIRO peaks marked by integers. (b) PIRO order $j$ vs $1/B$ (filled circles). Linear fit yields $s\simeq 3.4\mathrm{km}/\mathrm{s}$. Open circle marks the extra peak (cf. $\downarrow$ in Fig. 2).

Figure 2

Magnetoresistivity $\rho (B)$ at different temperatures, from 2.0 K (bottom trace) to 6.0 K (top trace), in 0.25 K increments. Traces are not vertically offset. Integers at the bottom trace mark the order $j$ of the PIRO peaks.

Figure 3

(a) Inverse mobility $1/\mu$ vs $T$. (b) Total mobility $\mu$ (open circles), impurity mobility ${\mu }^{\mathrm{im}}$ (dotted line) and acoustic-phonon mobility ${\mu }^{\mathrm{ph}}$ (filled circles) vs $T$.

Figure 4

(a) PIRO amplitude at $j=1$, 2, and 3 vs $T$. Curves are calculated using Eq. (1) for $\lambda =4.1$ and $\alpha =1.8\pm 0.2$. (b) Optimal temperature $T_0^2$ vs $B$.