Photo-induced valence change of the sulfur atom in an L-cysteine thin film grown on a silver metal substrate in a saliva-emulated aqueous solution

被引：2

作者：

Tsujibayashi, Toru ^{[1
]}

Azuma, Junpei ^{[2
]}

Yamamoto, Isamu ^{[2
]}

Takahashi, Kazutoshi ^{[2
]}

Kamada, Masao ^{[2
]}

机构：

[1] Osaka Dent Univ, Dept Phys, Hirakata, Osaka 5731121, Japan

[2] Saga Univ, Synchrotron Light Applicat Ctr, Saga 8408502, Japan

来源：

APPLIED PHYSICS LETTERS | 2015年 / 106卷 / 17期

基金：

日本学术振兴会;

关键词：

ADSORPTION; SPECTROSCOPY; MEMORY;

D O I：

10.1063/1.4919002

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

A thin film of L-cysteine (HSCH2CH(NH2) COOH) is grown on a silver substrate in saliva-emulated aqueous solution. X-ray photoemission spectroscopic measurements have revealed that the sulfur atom shows valence change under IR laser irradiation at 825 nm. The valence change maintains for about a minute at room temperature and more than an hour between 110 and 250K after stopping the laser irradiation. It is not observed at all at temperatures lower than 110 K. This temperature-dependent behavior indicates that the photo-excited electronic change should be accompanied by a conformational change in the L-cysteine molecule. It is strongly suggested that the reversible valence change of the sulfur atom is applicable to a memory used around room temperature. (C) 2015 AIP Publishing LLC.

引用

页数：4