Free current carriers in a medium make a contribution to its dielectric coefficient. The present experiment utilizes this effect to determine the effective masses of electrons and holes in germanium by measuring the microwave dielectric coefficient at several temperatures. The dielectric coefficient was determined by measuring the complex transmission coefficient at 24.15 kilomegacycles/sec through a thin slab of germanium. The effective mass for electron was $(0.09\mathrm{}\pm 0.05)m_0$; for holes it was $(0.30\mathrm{}\pm 0.05)m_0$.

• Received 3 March 1955

DOI:https://doi.org/10.1103/PhysRev.98.1761