Characteristics of optical recording on thin films of quaternary glasses Cu-As-Se-I

Abstract

The characteristics of optical recording and changes in the hologram parameters of the amorphous quaternary system Cu-As-Se-I are described. The dependence of the relative contrast of recording on the exposure and transparency properties of the film before and after erasure is the basis for discussion of these processes. Investigation into the dependence of diffraction efficiency of the holograms indicates that these quantities are determined by the thin film composition. IntroductionSome amorphous semiconducting materials have recently been studied as potential media for storing optical information. One of the fundamental problems is the reversibility of these processes, and the mode of erasing the optical pulses recorded. Earlier investigations of photoinduced processes in amorphous chalcogenide semiconductors (ChAS) have shown that these materials possess a relatively high resolution, reversibility of recording, and other properties that are of importance for their use in holography and for equipment for optical treatment of information [1, 2] (Table I).A series of previous experiments has been conducted on a very wide class of multicomponent amorphous systems: As-S, As-Se, M-As-B w, As-BW t, and M-As Se-I (M = metal, B w = S or Se) [3][4][5][6]. It has been observed that practically all these glasses are, to a smaller or greater extent, photosensitive to a certain wavelength of laser radiation, and the relevant parameters are dependent on the composition of the glass and conditions of its preparation. Four-component systems offer special possibilities because one can substantially influence the properties of the system simply by changing the ratio of their components. This is primarily concerned with the spectral interval of photosensitivity and characteristics of the recorderasure processes. It should be pointed out that a relatively complex technology of obtaining quaternary glasses and of thin films on their bases have been the reason why the processes of optical recording in these systems have received relatively little attention.We report here the results of our investigations of the optical recording processes and characteristics of holograms in the Cu-As-Se-I system.

Refractive-index dispersion and the optical-absorption edge of wedge-shaped thin films of metal - chalcogenide glasses

“…Some previous investigations [4][5][6] have shown that the introduction of Cu into the As 2 Se 3 glass causes a substantial increase in the efficiency (contrast, photosensitivity, reversibility and diffractive efficiency) of optical recording on thin films of Cu x (As 2 Se 3 ) 100−x , x < 20 at.%. It can be supposed that the Cu atoms interacting with Se atoms produce an additional number of weak As-Se bonds and weak As 'dangling' bonds, which are responsible for the process of optical recording.…”

Studies on structural, electrical, and optical properties of Cu doped As–Se–Te chalcogenide glasses

“…͑1͒, and ph is the characteristic phonon frequency taken as 10 12 Hz, a typical value in amorphous materials. ͑1͒, and ph is the characteristic phonon frequency taken as 10 12 Hz, a typical value in amorphous materials.…”

“…1 Moreover, ChG glasses are conducive for use in fiber optics and integrated optics since they have many unique optical properties and exhibit a good transparency in the infrared region. Some previous investigations 12 have shown that the introduction of Cu into the As 2 Se 3 glass causes a substantial increase in the efficiency ͑contrast, photosensitivity, reversibility, and diffractive efficiency͒ of optical recording on thin films of Cu x ͑As 2 Se 3 ͒ 100−x with x Ͻ 20 at. 9 As 2 S 3 and As 2 Se 3 have traditionally been used for mid-IR fibers with transmission windows up to 12 m. In order to further the transmission window into the far-IR range ͑Ͼ15 m͒, the S or Se atoms, which cause far-IR absorption due to As-S or As-Se bond vibration, can be replaced by heavier counterparts such as Te or transition metals.…”

Dispersion of Refractive Index of Non-Crystalline Chalcogenides in Cu-As-Se System

“…The chalcogenide glass film based registering media have unique properties, such as amorphous structure, high chemical resistivity, and a wide range of spectral sensitivity. There are numerous potential applications in microelectronics, high-density information recording, holography [8][9][10], and other areas.…”