A Nanographite Film-Based Fast Response Detector for Intense Laser Radiation

Abstract

A simple high-speed photodetector of high-power laser radiation, based on the optical rectification effect, is described. It operates without an external power source. A nanographite film deposited onto a silicon substrate using the plasmochemical deposition technique and having two conducting surface electrodes is used as the photodetector's photosensitive element. The performance of this device was demonstrated by detecting pulsed laser radiation in a spectral range of 0.266-1.9 µ m using the second, third, and fourth harmonics of radiation from an YAG : Nd 3+ laser with passive Q -switching and radiation from light oscillators based on stimulated Raman scattering in compressed hydrogen. It was shown that the photodetector sensitivity is proportional to the optical radiation frequency and its response time is shorter than 0.5 ns.

Wavelength‐Dependent Photocurrent Generation Efficiency in the Carbon Nanowall Films

“…[25,42,43,50,51] Previously we have shown that the photocurrent pulses can be excited in the carbon nanowall (CNW) films (also called as "nanographite (NG) films") due to PDE and SPGE under irradiation by the nanosecond laser pulses. [42] Wide spectral range of light absorption in CNW films, spanning from ultraviolet (UV) [52] to far infrared (IR) and even to millimeter wavelength (Terahertz THz) range, [42,53] allows creation of multispectral, high-speed photodetectors [54] sensitive to radiation polarization and operating at room and higher temperature. [55,56] However, practical application of this type of detectors requires further optimization, presumably achievable via extensive studies of its sensitivity dependence on properties of used material.…”

Nanographite Films: Structure and Properties

“…Recently, different groups of researchers have tested various methods of fabricating films of nanographites [3][4][5][6][7]. The method of growing nanographites on a silicon substrate by plasma chemical vapor deposition from a mixture of methane and hydrogen was mastered to study their optoelectronic characteristics [3][4][5].…”

“…Recently, different groups of researchers have tested various methods of fabricating films of nanographites [3][4][5][6][7]. The method of growing nanographites on a silicon substrate by plasma chemical vapor deposition from a mixture of methane and hydrogen was mastered to study their optoelectronic characteristics [3][4][5]. The authors of [6] reported on forming nanographite film by exposing a glass plate in the electrochemically prepared water-based nanographite colloid with simultaneous ultrasonic treatment of the solution.…”

“…Nanographite assembled films were also grown from a stable dispersion of graphite particles obtained from natural graphite by ultrasonic crushing in various solvents [7]. However, one should mention that although in all these papers [3][4][5][6][7] graphite particles in the films had a thickness of several nanometers, their average lateral sizes were much greater than the corresponding nanographite size (≈3 nm), for which the theory predicts the maximum contribution of boundary π-electron states in the electronic structure near the Fermi level [8] and, as a result, fundamentally new physical and chemical properties of particles [1]. So the importance of the work aimed at formation and study of film structures of graphite particles with nanometric lateral sizes is evident.…”