Infrared dyes for optical storage

Abstract

There is current interest in developing optical storage materials that can be written with GaAlAs lasers. Dyes which absorb strongly at those wavelengths are potential candidates for this application due to their attractive thermal properties. Through optical and thermal modelling, the properties that are necessary if they are to be writeable at energies of ?1 nJ are examined. A specific class of infrared absorbing dyes, squarylium, is discussed and preliminary data on optical characteristics, writing energy, and stability are presented.

Linear Photophysics and Femtosecond Nonlinear Spectroscopy of a Star-Shaped Squaraine Derivative with Efficient Two-Photon Absorption

“…Reagents and conditions for the synthesis of 1 are presented in Figure 1. The star-shaped squaraine derivative 1 was accomplished by first synthesizing the azide-containing unsymmetrical squaraine dye (1)(2)(3)(4)(5)(6) and then coupling this to 1,3,5-tris(2-propynyloxy)benzene (1-7) via click chemistry. Initially, the synthesis of precursors 1-4 and 1-5 are based on the general reactivity of phloroglucinol with secondary amines through its keto tautomer in n-butanol/toluene mixture at reflux temperature.…”

“…Squaraine molecules are a promising class of chromophores with potential applications in a number of scientific and technological areas such as organic electronics, − optical data storage, , chemosensing, − nonlinear optics, − photodynamic therapy, − and one- and two-photon fluorescence probes. − In this regard, the synthesis of new squaraine derivatives and the investigation of their main photophysical, photochemical, and nonlinear optical properties are subjects of intense interest for a variety of optical applications. Squaraines are neutral molecules with a resonance-stabilized zwitterionic structure, , and typical D-A-D type of electronic distribution, , where D and A stand for electron-donating terminal groups and electron-deficient (electron acceptor) central oxocyclobutenolate core, respectively.…”

Synthesis and Nanoarchitectonics of Novel Squaraine Derivatives for Organic Photovoltaic Devices

“…We developed new small molecule photoabsorbers that are based on squaraines (SQ). Even though squaraines have been previously applied as xerographic photoreceptors [ 15 ], an optical recording medium [ 16 ], electro-light-emitting diodes [ 17 ], and nonlinear optical devices [ 18 ] on behalf of their unique electronic structures and optical properties, their application in a group of organic photovoltaic devices (OPV) and related devices is still scarce in the literature [ 19 , 20 ]. SQ’s advantages, when considering applications as donor materials in OPVs, are high absorption coefficients, where bandwidths can be adjusted in the visible and NIR range, as well as high photochemical and thermal stability [ 21 ].…”

Pyran-Squaraine as Photosensitizers for Dye-Sensitized Solar Cells: DFT/TDDFT Study of the Electronic Structures and Absorption Properties

“…The squaraine class of molecules is well known for its spectroscopic characteristics. The photochemical and 2 International Journal of Photoenergy photophysical properties of these dyes have been studied extensively [20][21][22][23][24] because of their many technological applications in copiers and laser printers [25][26][27], organic optical disks [28], and organic solar cells. The general structure of symmetric squaraine can be described as a D-A-D system, where D is an electron donor and A is the central squaric ring, which plays as an electron acceptor.…”