Abstract The recording density of multilevel photochromic memory is limited by the signal-to-noise ratio (SNR) of the readout signal. In this paper, shot noise and material noise are investigated through theoretical analysis of SNR. When the bandwidth of a system is less than 1MHz, the material noise takes a prominent position; when the bandwidth of the system is more than 10MHz, the shot noise becomes dominant. The thickness of recording layer can be optimized to maximize the SNR and reduce the influence of the bandwidth of the system on SNR.
Received: 14 December 2005
Revised: 24 April 2006
Accepted manuscript online:
Fund: Project supported by the State Key Development Program For Basic Research of China (Grant No 19990330) and the National Natural Science Foundation of China (Grant No 60577035).
Cite this article:
Zhang Qi-Cheng(张启程), Ni Yi(倪屹), Xu Duan-Yi(徐端颐), and Hu Heng(胡恒) Restriction of shot noise and material noise in a multilevel photochromic memory on signal-to-noise ratio 2006 Chinese Physics 15 1783
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