Rewritable optical-disk fabrication with an optical recording material made of naphthalocyanine and polythiophene

Abstract

A novel rewritable optical disk that uses an optical recording material made of naphthalocyanine and polythiophene as the recording layer is described. In this system the complex refractive index of the recording material changes reversibly, depending on the aggregation states of naphthalocyanine induced by a conformation change of the polythiophene matrix. After recording, the imaginary part of the refractive index of the recording material increases to three times that of the unrecorded part, at a wavelength of 790 nm at which a semiconductor laser emits light. The fabricated polythiophene naphthalocyanine optical disk shows a high reflectivity of 58% and a large readout modulation amplitude (I(11)/I(top)) of 0.63. It is confirmed that the polythiophene/naphthalocyanine optical disk can be played back on conventional compact-disc players even after ten cycles of rewriting.

Electronic Structure of Metal-Free Porphyrazines in Thin Films

“…Several studies were concerned with extended porphyrazine compounds that have additional aromatic rings attached to the skeleton of the porphyrazine molecule. 3,4 The wide interest for these molecules, [4][5][6][7][8][9][10][11] ranging from biology to technological applications, clearly demands a detailed understanding of their electronic structure. A suitable technique by which this information may be accessed is photoelectron spectroscopy.…”

“…The wide interest for these molecules, − ranging from biology to technological applications, clearly demands a detailed understanding of their electronic structure. A suitable technique by which this information may be accessed is photoelectron spectroscopy.…”

Z-scan study of thermal nonlinearities in silicon naphthalocyanine-toluene solution with the excitations of the picosecond pulse train and nanosecond pulse

“…In Eqs. (7) and (8), I and φ changes are contributed to the one-photon excitations S 0 →| ν)S 1 , S 1 →| ν)S 2 , and T 1 →| ν)T 2 represented by their first three terms. σ a in Eq.…”

“…The population densities required in Eqs. (7) and (8) are functions of both space and time. The dynamic behaviors can be obtained by calculating the rate equations (9) to (11).…”

“…These molecules show potential in optical-limiting applications due to their large excited-state absorption cross sections in both singlet and triplet manifolds within the visible spectrum [3][4][5][6]. They are also good candidates for optical recording materials because of their large nonlinear refraction in the infrared regime [7,8]. Using the Z-scan technique, we characterized the nonlinear absorption and refraction properties of a silicon naphthalocyanine (Si(OSi(n-hexyl) 3 ) 2 , dubbed SiNc)-toluene solution at 532 nanometer (nm).…”