标题： 二维各向异性重费米子在AlAs量子阱中的磁等离子体激发 显示英文标题

标题： Magnetoplasma excitations of two-dimensional anisotropic heavy fermions in AlAs quantum wells

摘要： 等离子体和磁等离子体激发在各向异性重费米子二维系统中的谱首次被研究。 在低电子密度下，受应力的AlAs量子阱盘状样品的微波吸收谱显示两个由频率间隙分隔的等离子体共振。 这两个等离子体共振对应电子质量主值$(1.10 \pm 0.05) m_0$和$(0.20 \pm 0.01) m_0$。 观测结果对应于单个谷强各向异性费米面的情况。 已确定电子密度增加会导致第二个谷的填充，表现为等离子体谱的剧烈变化。 我们直接从两个等离子体频率的比值中确定了每个谷中的电子密度和谷间分裂能量。 显示英文摘要

摘要： The spectra of plasma and magnetoplasma excitations in a two-dimensional system of anisotropic heavy fermions were investigated for the first time. The spectrum of microwave absorption by disk-like samples of stressed AlAs quantum wells at low electron densities showed two plasma resonances separated by a frequency gap. These two plasma resonances correspond to electron mass principle values of $(1.10 \pm 0.05) m_0$ and $(0.20 \pm 0.01) m_0$. The observed results correspond to the case of a single valley strongly anisotropic Fermi surface. It was established that electron density increase results in population of the second valley, manifesting itself as a drastic modification of the plasma spectrum. We directly determined the electron densities in each valley and the inter-valley splitting energy from the ratio of the two plasma frequencies.