R. H. Willens

NEW PERMANENT MAGNET MATERIALS.

New permanent magnet materials containing rare‐earth elements (RE) have been discovered. For the most part, these alloys are based on the hexagonal intermetallic compounds, Co5RE. Replacement of cobalt with copper in some of these rare‐earth compounds results in solid materials with substantial permanent magnet properties. Coercive forces as high as 28,700 Oe have been obtained in heat‐treated samples of alloys in the Co5Sm–Cu5Sm system.

Lateral photoeffect in thin amorphous superlattice films of Si and Ti grown on a Si substrate

The lateral photoeffect in a new type of amorphous superlattice film, consisting of 6 A of Ti and 13 A of Si grown on a Si substrate, is discussed. The photovoltage varies extremely linearly with light spot position and can thus be used in accurate position sensitive detectors.

Photoelectronic and electronic properties of Ti/Si amorphous superlattices

Amorphous Ti/Si superlattices have been prepared by electron beam evaporation. These superlattices exhibit electronic and photoelectronic properties which can be used in a variety of different types of devices. The photovoltaic output from this structure is greatly enhanced by deposition on Si substrates with electrical contacts made only to the superlattice film. The mechanism for the photovoltaic signals and illustrations of different types of devices are discussed.

High‐resolution photovoltaic position sensing with Ti/Si superlattices

A detector to sense the position of a beam of light with a resolution of less than 100 A has been fabricated with a Ti/Si amorphous superlattice on p‐type Si. There are two regions of photovoltaic sensitivity, a low sensitivity region having a response of 1.6 mV/mm and a high sensitivity region having 1.5 mV/μm. This novel detector can sense the light spot position over large lateral dimensions, while the high central sensitivity region would permit servo driving to a null position with a high degree of precision. These characteristics also suggest the use of this device in a variety of other photonic transducers.

Wavelength dependence of the lateral photovoltage in amorphous superlattice films of Si and Ti

Experiments are reported on the lateral photoeffect in a novel type of amorphous superlattice consisting of 6 A of Ti and 13 A of Si grown on Si substrate. The spectral, temperature, bias voltage, and time dependences have been measured for this new position sensitive detector.