Photonic switching based on the photoinduced birefringence in bacteriorhodopsin films

Abstract

Photoinduced birefringence in bacteriorhodopsin films was investigated using pump–probe method and its application for photonic switching explored. A diode-pumped second-harmonic YAG laser was used as a pumping beam and a diode laser at λ=660 nm was used as a probing beam. The pump and probe beams overlap at the sample. Without the pumping beam, the probing light cannot transmit the analyzer to the detector. However, due to the photoinduced anisotropy, a portion of the probing light is detected when the pumping beam is present. Since λ=660 nm is far from the absorption peak (∼570 nm) of the ground state, the photoinduced birefringence predominates. Using the intensity-dependent photoinduced birefringence in a bacteriorhodopsin film, we have demonstrated a photonic switch with ∼1000:1 contrast ratio, ∼0.6 s rise time and ∼1.5 s decay time.

Time-dependent all-optical logic-gates with bacteriorhodopsin film

“…Various types of logic gates using bR film have been proposed, such as alloptical logic operations by the modulation property of bR film [3], logic operations with polarization properties of the phase conjugate beams in degenerate four-wave mixing (DFWM) [4], the logic operation and all-optical switches by the intermediate states in bR film [5][6][7][8]. Optical computing is one important portion in optical information processing.…”

Enhancement of speed of digital operation in bacteriorhodopsin based photonic switch

“…In this paper, we theoretically realize fast digital operation in Mz frequency range, in bR-based photonic switch. The present speed of digital operation in Mz is much higher in comparison to earlier reported speed in kHz [5][6][7][8][9][10][11][12][13][14][15][16][17]. The switching response has also been shown to be improved by exciting the switch with an additional bias laser beam.…”

“…Most of the photonic applications of bR have been proposed by utilizing its M and O intermediates, having lifetimes in the range of milliseconds [5,7]. Photonic switching in bR has also been reported experimentally and theoretically considering various mechanisms, however, with slow response time in the range of ms-s [5][6][7][8][9][10][11][12][13][14][15][16][17], which is not adequate for practical applications. Hence, exploitation of earlier faster photo-intermediates for realization of fast switching operation in bR seems to be an optimistic effort.…”

All-optical image switch based on bacteriorhodopsin film

“…It has been used in various logic operations and image processing [1][2][3][4][5][6][7], and one of extensive applications is photonic switches [7][8][9][10][11]. All-optical switches are produced by using the various stable characteristics of bR film, such as the photocycle of intermediate states [1,3,11], photoinduced birefringence [10], and photoinduced anisotropy in bR film [9]. Recently, especial attention is given to the applications of the dynamic characteristics of bR film, such as the novelty filter [12], time-dependent logic gates making use of two-wave [13] or muti-wave couple [14], and the intensity-dependent image switch based on mutiwave couple in bR film [15].…”