Abstract
Seven new absorption lines have been observed at 1.5°K by transmitting unpolarized far-infrared light through a thin, single crystal of bismuth in a magnetic field . Both the propagation direction and were along the trigonal axis and perpendicular to the sample face. We used an interference spectrometer built by P. L. Richards covering frequencies between 13 and 85 together with a superconducting solenoid producing fields up to 50 kG. All seven lines lie well below the cyclotron frequency for either electrons or holes. As is increased, certain lines narrow and disappear one by one until at 50 kG only three remain. As is tilted a few degrees away from the trigonal axis some of these lines split with a strong angular dependence while others remain almost unaffected. We attribute these lines to spin and combination resonances of the conduction electrons. From the fields at which particular resonances disappear, energy-level assignments can be made. These assignments and the observed splittings are compared with calculated values based on published masses.
- Received 7 June 1965
DOI:https://doi.org/10.1103/PhysRev.140.A925
©1965 American Physical Society